{"id":"CVE-2026-48095","aliases":["ALPINE-CVE-2026-48095","DEBIAN-CVE-2026-48095","EUVD-2026-34838","MGASA-2026-0238","SUSE-SU-2026:22347-1","SUSE-SU-2026:2696-1","UBUNTU-CVE-2026-48095","openSUSE-SU-2026:10942-1","openSUSE-SU-2026:21038-1"],"status":"published","title":"GHSL-2026-140_7-Zip: 7-Zip has a heap buffer overflow via NTFS compressed stream buffer under-allocation","description":"7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 \u003c\u003c (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog \u003e= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.","severity":{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.01116,"percentile":0.66305,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":true,"fix_available":true},"cwes":["CWE-190","CWE-787"],"published":"2026-06-03T00:00:00Z","modified":"2026-10-17T13:00:22Z","exploits":[{"source":"pocgithub","id":"HORKimhab/CVE-2026-48095","title":"HORKimhab/CVE-2026-48095","date":"2026-05-26","url":"https://github.com/HORKimhab/CVE-2026-48095"}],"fixes":[{"ecosystem":"Alpine:v3.24","package":"7zip","fixed_in":["26.01-r0"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"7zip","fixed_in":["22.01+really26.01+dfsg-0+deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"7zip","fixed_in":["26.01+dfsg-1"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"p7zip","fixed_in":["16.02+really26.01+dfsg-0+deb12u1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"p7zip","fixed_in":["16.02+transitional.1"],"sources":["osv"]},{"ecosystem":"Mageia:10","package":"7zip","fixed_in":["26.02-1.mga10"],"sources":["osv"]},{"ecosystem":"openSUSE:Tumbleweed","package":"7zip","fixed_in":["26.01-1.1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Alpine:v3.24","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-r0"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"22.01+really26.01+dfsg-0+deb12u1"}]}],"versions":["22.01+dfsg-10~exp1","22.01+dfsg-8","22.01+dfsg-8+deb12u1","22.01+dfsg-9","22.01+really25.01+dfsg-0+deb12u1"]},{"source":"osv","ecosystem":"Debian:13","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["24.09+dfsg-8","25.00+dfsg-1","25.01+dfsg-1","25.01+dfsg-1~deb13u1","25.01+dfsg-1~deb13u1~bpo12+1","25.01+dfsg-1~deb13u2","25.01+dfsg-2","25.01+dfsg-3","25.01+dfsg-4","25.01+dfsg-5","26.00+dfsg-1","26.00+dfsg-2","26.00+dfsg-3","26.00+dfsg-4","26.00+dfsg-5","26.00+dfsg1-1","26.00+dfsg1-2","26.00+dfsg1-3","26.01+dfsg-1","26.01+dfsg-2","26.01+dfsg-3","26.02+dfsg-1","26.02+dfsg-2","26.02+dfsg-3","26.03+dfsg-1","26.03+dfsg-2","26.03+dfsg-3"]},{"source":"osv","ecosystem":"Debian:14","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01+dfsg-1"}]}],"versions":["24.09+dfsg-8","25.00+dfsg-1","25.01+dfsg-1","25.01+dfsg-1~deb13u1","25.01+dfsg-1~deb13u1~bpo12+1","25.01+dfsg-1~deb13u2","25.01+dfsg-2","25.01+dfsg-3","25.01+dfsg-4","25.01+dfsg-5","26.00+dfsg-1","26.00+dfsg-2","26.00+dfsg-3","26.00+dfsg-4","26.00+dfsg-5","26.00+dfsg1-1","26.00+dfsg1-2","26.00+dfsg1-3"]},{"source":"osv","ecosystem":"Debian:12","package":"p7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"16.02+really26.01+dfsg-0+deb12u1"}]}],"versions":["16.02+dfsg-8","16.02+really25.01+dfsg-0+deb12u1"]},{"source":"osv","ecosystem":"Debian:13","package":"p7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"16.02+transitional.1"}]}]},{"source":"osv","ecosystem":"Mageia:10","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.02-1.mga10"}]}]},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 16.0","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-160000.1.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP applications 16.0","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-160000.1.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Module for Basesystem 15 SP7","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP4-LTSS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP5-ESPOS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise High Performance Computing 15 SP5-LTSS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 15 SP4-LTSS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 15 SP5-LTSS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server 15 SP6-LTSS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15 SP4","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15 SP5","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"SUSE:Linux Enterprise Server for SAP Applications 15 SP6","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-150400.9.6.1"}]}],"bundled":8},{"source":"osv","ecosystem":"Ubuntu:14.04:LTS","package":"p7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["9.20.1~dfsg.1-4","9.20.1~dfsg.1-4+deb7u1build0.14.04.1","9.20.1~dfsg.1-4+deb7u2build0.14.04.1","9.20.1~dfsg.1-4+deb7u3build0.14.04.1"]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"p7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["9.20.1~dfsg.1-4.2","9.20.1~dfsg.1-4.2ubuntu0.1"]},{"source":"osv","ecosystem":"Ubuntu:18.04:LTS","package":"p7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["16.02+dfsg-4","16.02+dfsg-5","16.02+dfsg-6"]},{"source":"osv","ecosystem":"Ubuntu:20.04:LTS","package":"p7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["16.02+dfsg-7","16.02+dfsg-7build1"]},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"p7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["16.02+dfsg-8"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["21.03~beta+dfsg-6","21.04~beta+dfsg-1","21.06+dfsg-1","21.07+dfsg-1","21.07+dfsg-2","21.07+dfsg-3","21.07+dfsg-4","21.07+dfsg-4ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["23.01+dfsg-3","23.01+dfsg-7","23.01+dfsg-8","23.01+dfsg-11","23.01+dfsg-11ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["24.09+dfsg-7","24.09+dfsg-8","25.00+dfsg-1","25.01+dfsg-1","25.01+dfsg-2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["26.00+dfsg-1","26.01+dfsg-2","26.01+dfsg-3","26.02+dfsg-1","26.02+dfsg-2"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["25.01+dfsg-2","25.01+dfsg-3","25.01+dfsg-4","25.01+dfsg-5","26.00+dfsg-1"]},{"source":"osv","ecosystem":"openSUSE:Tumbleweed","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-1.1"}]}]},{"source":"osv","ecosystem":"openSUSE:Leap 16.0","package":"7zip","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"26.01-160000.1.1"}]}],"bundled":8}],"products":[{"vendor":"7-zip","product":"7-zip"},{"vendor":"mcmilk","product":"7-zip"}],"references":[{"url":"https://securitylab.github.com/advisories/GHSL-2026-140_7-Zip/","tags":["x_refsource_CONFIRM","exploit","Exploit","Third Party Advisory","advisory","report"]},{"url":"https://sourceforge.net/p/sevenzip/discussion/45797/thread/555e132ba4","tags":["x_refsource_MISC","Product","Release Notes"]},{"url":"https://security.alpinelinux.org/vuln/CVE-2026-48095","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-48095","tags":["advisory"]},{"url":"https://advisories.mageia.org/MGASA-2026-0238.html","tags":["advisory"]},{"url":"https://bugs.mageia.org/show_bug.cgi?id=35647","tags":["report"]},{"url":"https://lists.opensuse.org/archives/list/security-announce@lists.opensuse.org/message/MKEOLTFHUWP7BQ2ILOTOFFTHHM3IADU3/","tags":["web"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/BAJUM226JIQJF4PYM6EWAVY5M7POD652/","tags":["web"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/OHMTNNKWIDXZP5647A5C27UDXK33KG4G/","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-202622347-1/","tags":["advisory"]},{"url":"https://bugzilla.suse.com/1267421","tags":["report"]},{"url":"https://bugzilla.suse.com/1267858","tags":["report"]},{"url":"https://bugzilla.suse.com/1267859","tags":["report"]},{"url":"https://bugzilla.suse.com/1267860","tags":["report"]},{"url":"https://bugzilla.suse.com/1267861","tags":["report"]},{"url":"https://bugzilla.suse.com/1267862","tags":["report"]},{"url":"https://bugzilla.suse.com/1267863","tags":["report"]},{"url":"https://bugzilla.suse.com/1267864","tags":["report"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48092","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48095","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48101","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48102","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48103","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48104","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48111","tags":["web"]},{"url":"https://www.suse.com/security/cve/CVE-2026-48112","tags":["web"]},{"url":"https://www.suse.com/support/update/announcement/2026/suse-su-20262696-1/","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-48095","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-48095","tags":["report"]},{"url":"","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-48095","title":"GHSL-2026-140_7-Zip: 7-Zip has a heap buffer overflow via NTFS compressed stream buffer under-allocation","description":"7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 \u003c\u003c (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog \u003e= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.","status":"published","published":"2026-06-05T13:57:43.772Z","modified":"2026-06-08T19:10:46.668Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-787","CWE-190"],"updated_at":"2026-11-02T14:19:47.998488Z"}],"euvd":[{"id":"EUVD-2026-34838","description":"7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 \u003c\u003c (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog \u003e= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.","status":"published","published":"2026-06-05T13:57:43Z","modified":"2026-06-08T19:10:46Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T18:20:48.375828Z"}],"nvd":[{"id":"CVE-2026-48095","description":"7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 \u003c\u003c (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog \u003e= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.","status":"published","published":"2026-06-05T15:16:53.52Z","modified":"2026-06-17T10:54:50.997Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-190","CWE-787"],"updated_at":"2026-11-02T14:12:22.371367Z"}],"osv":[{"id":"ALPINE-CVE-2026-48095","description":"7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 \u003c\u003c (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog \u003e= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.","status":"published","published":"2026-06-05T15:16:53.52Z","modified":"2026-10-01T02:17:49.3171704Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:27:50.764331Z"},{"id":"DEBIAN-CVE-2026-48095","description":"7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 \u003c\u003c (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog \u003e= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.","status":"published","published":"2026-06-05T15:16:53.52Z","modified":"2026-10-01T03:03:15.951637315Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:56.444225Z"},{"id":"UBUNTU-CVE-2026-48095","description":"7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 \u003c\u003c (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog \u003e= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching \"NTFS    \" at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.","status":"published","published":"2026-06-05T15:16:00Z","modified":"2026-10-17T13:00:22.081380991Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T16:56:33.391918Z"},{"id":"MGASA-2026-0238","title":"Updated 7zip packages fix a security vulnerability","description":"7-Zip has a heap buffer overflow via NTFS compressed stream buffer\nunder-allocation. (CVE-2026-48095)\n","status":"published","published":"2026-07-09T16:46:08Z","modified":"2026-07-09T17:00:04.415406533Z","updated_at":"2026-11-02T15:49:43.795591Z"},{"id":"openSUSE-SU-2026:10942-1","title":"7zip-26.01-1.1 on GA media","description":"These are all security issues fixed in the 7zip-26.01-1.1 package on the GA media of openSUSE Tumbleweed.","status":"published","published":"2026-06-03T00:00:00Z","modified":"2026-06-04T09:00:04.609328737Z","updated_at":"2026-11-02T16:58:38.95195Z"},{"id":"openSUSE-SU-2026:21038-1","title":"Security update for 7zip","description":"This update for 7zip fixes the following issues\n\nUpdate to 26.01:\n\n- CVE-2026-48092: Information disclosure in 32-bit builds due to heap memory disclosure (bsc#1267858).\n- CVE-2026-48095: Heap buffer overflow via NTFS compressed stream buffer under-allocation (bsc#1267421).\n- CVE-2026-48101: Information Disclosure via uninitialized memory in UEFI capsule parser (bsc#1267859).\n- CVE-2026-48102: Information disclosure and denial of service via crafted UDF image (bsc#1267860).\n- CVE-2026-48103: off-by-one heap out-of-bounds read (bsc#1267861).\n- CVE-2026-48104: Uninitialized heap read in SquashFS archive handler (bsc#1267862).\n- CVE-2026-48111: off-by-one out-of-bounds read in ParseDepedencyExpression function (bsc#1267863).\n- CVE-2026-48112: heap out-of-bounds read in BSD SYMDEF parser (bsc#1267864).\n\nChanges:\n\n * linux version of 7-Zip can use huge pages (2 MB pages). It can\n increase compression speed for 10% for 7z/xz/LZMA/LZMA2 compression.\n * new -spo[d|c|r] switch specifies the path generation mode for\n the output directory for archive extraction. The output directory\n path is generated from the path specified in the -o{dir_path}\n switch and the name of the archive being unpacked.\n -spod : for Linux/Posix/macOS: -o{dir_path} specifies the direct\n path to the output directory. The asterisk (*) character\n in {dir_path} will not be replaced by the archive name.\n -spoc : 7-Zip will concatenate the path specified in -o{dir_path}\n with the archive name to form the final path to the output\n directory.\n -spor : 7-Zip will replace asterisk (*) character in the path\n specified in the -o{dir_path} with the archive name.\n This is the default option.\n * some bugs were fixed.\n- Update to 26.00:\n * improved code for ZIP, CPIO, RAR, UFD, QCOW, Compound.\n * 7-Zip File Manager: improved sorting order of the file list.\n It uses file name as secondary sorting key.:\n * 7-Zip File Manager: improved Benchmark to support systems with more than\n 64 CPU threads.\n * bug fixed: 7-Zip could not correctly extract TAR archives containing sparse\n files\n","status":"published","published":"2026-06-23T12:46:58Z","modified":"2026-06-30T18:24:37.043123175Z","updated_at":"2026-11-02T16:58:41.885092Z"},{"id":"SUSE-SU-2026:22347-1","title":"Security update for 7zip","description":"This update for 7zip fixes the following issues\n\nUpdate to 26.01:\n\n- CVE-2026-48092: Information disclosure in 32-bit builds due to heap memory disclosure (bsc#1267858).\n- CVE-2026-48095: Heap buffer overflow via NTFS compressed stream buffer under-allocation (bsc#1267421).\n- CVE-2026-48101: Information Disclosure via uninitialized memory in UEFI capsule parser (bsc#1267859).\n- CVE-2026-48102: Information disclosure and denial of service via crafted UDF image (bsc#1267860).\n- CVE-2026-48103: off-by-one heap out-of-bounds read (bsc#1267861).\n- CVE-2026-48104: Uninitialized heap read in SquashFS archive handler (bsc#1267862).\n- CVE-2026-48111: off-by-one out-of-bounds read in ParseDepedencyExpression function (bsc#1267863).\n- CVE-2026-48112: heap out-of-bounds read in BSD SYMDEF parser (bsc#1267864).\n\nChanges:\n\n * linux version of 7-Zip can use huge pages (2 MB pages). It can\n increase compression speed for 10% for 7z/xz/LZMA/LZMA2 compression.\n * new -spo[d|c|r] switch specifies the path generation mode for\n the output directory for archive extraction. The output directory\n path is generated from the path specified in the -o{dir_path}\n switch and the name of the archive being unpacked.\n -spod : for Linux/Posix/macOS: -o{dir_path} specifies the direct\n path to the output directory. The asterisk (*) character\n in {dir_path} will not be replaced by the archive name.\n -spoc : 7-Zip will concatenate the path specified in -o{dir_path}\n with the archive name to form the final path to the output\n directory.\n -spor : 7-Zip will replace asterisk (*) character in the path\n specified in the -o{dir_path} with the archive name.\n This is the default option.\n * some bugs were fixed.\n- Update to 26.00:\n * improved code for ZIP, CPIO, RAR, UFD, QCOW, Compound.\n * 7-Zip File Manager: improved sorting order of the file list.\n It uses file name as secondary sorting key.:\n * 7-Zip File Manager: improved Benchmark to support systems with more than\n 64 CPU threads.\n * bug fixed: 7-Zip could not correctly extract TAR archives containing sparse\n files\n","status":"published","published":"2026-06-23T12:43:00Z","modified":"2026-07-02T18:24:12.464330836Z","updated_at":"2026-11-02T15:54:03.080707Z"},{"id":"SUSE-SU-2026:2696-1","title":"Security update for 7zip","description":"This update for 7zip fixes the following issues\n\nUpdate to 26.01:\n\n- CVE-2026-48092: Information disclosure in 32-bit builds due to heap memory disclosure (bsc#1267858).\n- CVE-2026-48095: Heap buffer overflow via NTFS compressed stream buffer under-allocation (bsc#1267421).\n- CVE-2026-48101: Information Disclosure via uninitialized memory in UEFI capsule parser (bsc#1267859).\n- CVE-2026-48102: Information disclosure and denial of service via crafted UDF image (bsc#1267860).\n- CVE-2026-48103: off-by-one heap out-of-bounds read (bsc#1267861).\n- CVE-2026-48104: Uninitialized heap read in SquashFS archive handler (bsc#1267862).\n- CVE-2026-48111: off-by-one out-of-bounds read in ParseDepedencyExpression function (bsc#1267863).\n- CVE-2026-48112: heap out-of-bounds read in BSD SYMDEF parser (bsc#1267864).\n\nChanges:\n\n * linux version of 7-Zip can use huge pages (2 MB pages). It can\n increase compression speed for 10% for 7z/xz/LZMA/LZMA2 compression.\n * new -spo[d|c|r] switch specifies the path generation mode for\n the output directory for archive extraction. The output directory\n path is generated from the path specified in the -o{dir_path}\n switch and the name of the archive being unpacked.\n -spod : for Linux/Posix/macOS: -o{dir_path} specifies the direct\n path to the output directory. The asterisk (*) character\n in {dir_path} will not be replaced by the archive name.\n -spoc : 7-Zip will concatenate the path specified in -o{dir_path}\n with the archive name to form the final path to the output\n directory.\n -spor : 7-Zip will replace asterisk (*) character in the path\n specified in the -o{dir_path} with the archive name.\n This is the default option.\n * improved code for ZIP, CPIO, RAR, UFD, QCOW, Compound.\n * 7-Zip File Manager: improved sorting order of the file list.\n It uses file name as secondary sorting key.:\n * 7-Zip File Manager: improved Benchmark to support systems with more than\n 64 CPU threads.\n * bug fixed: 7-Zip could not correctly extract TAR archives containing sparse\n files\n","status":"published","published":"2026-06-30T09:10:04Z","modified":"2026-07-01T09:45:06.024787597Z","updated_at":"2026-11-02T15:54:04.519245Z"}]}}