{"id":"CVE-2026-122129","aliases":["DEBIAN-CVE-2026-122129","EUVD-2026-117083","GHSA-v896-hxw5-4767","UBUNTU-CVE-2026-122129"],"status":"published","title":"CESNET ipfixcol2 2.7.1 before 2.9.0 Memory Exhaustion via TCP LZ4 Decoder","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","severity":{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00401,"percentile":0.34789,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-789"],"published":"2026-11-04T20:36:49Z","modified":"2026-11-06T01:05:03Z","fixes":[{"ecosystem":"Debian:14","package":"ipfixcol2","fixed_in":["2.9.0-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:14","package":"ipfixcol2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.9.0-1"}]}],"versions":["2.8.0+20260519-1","2.8.0+20260519-2","2.8.0+20260701-1","2.8.0+20260701-2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"ipfixcol2","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.8.0+20260519-1","2.8.0+20260519-2","2.8.0+20260701-1"]}],"products":[{"vendor":"cesnet","product":"ipfixcol2"}],"references":[{"url":"https://github.com/CESNET/ipfixcol2/commit/1a199033eff847941353c5c039cb806a9ad8aa6f","tags":["patch","fix","report"]},{"url":"https://github.com/CESNET/ipfixcol2","tags":["product","package","report"]},{"url":"https://github.com/CESNET/ipfixcol2/releases/tag/v2.9.0","tags":["release-notes","advisory","report"]},{"url":"https://github.com/CESNET/ipfixcol2/blob/v2.8.0/src/plugins/input/tcp/src/Lz4Decoder.cpp#L126-L131","tags":["technical-description","article","report"]},{"url":"https://www.vulncheck.com/advisories/cesnet-ipfixcol2-2.7.1-before-2.9.0-memory-exhaustion-via-tcp-lz4-decoder","tags":["third-party-advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-122129","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-v896-hxw5-4767"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/122xxx/CVE-2026-122129.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-122129","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-122129","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-122129","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-122129","title":"CESNET ipfixcol2 2.7.1 before 2.9.0 Memory Exhaustion via TCP LZ4 Decoder","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","status":"published","published":"2026-11-04T20:36:49.66Z","modified":"2026-11-05T20:48:47.204Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-789"],"updated_at":"2026-11-05T21:25:05.838392Z"}],"euvd":[{"id":"EUVD-2026-117083","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","status":"published","published":"2026-11-04T20:36:49Z","modified":"2026-11-05T20:48:47Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-05T22:02:10.222428Z"}],"ghsa":[{"id":"GHSA-v896-hxw5-4767","title":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder:...","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","status":"published","published":"2026-11-04T21:32:31Z","modified":"2026-11-04T21:32:40Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"}],"cwes":["CWE-789"],"updated_at":"2026-11-04T21:42:46.194147Z"}],"nvd":[{"id":"CVE-2026-122129","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","status":"published","published":"2026-11-04T21:18:08.38Z","modified":"2026-11-05T21:18:42.657Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium","assessor":"secondary"}],"cwes":["CWE-789"],"updated_at":"2026-11-05T23:57:23.479749Z"}],"osv":[{"id":"CVE-2026-122129","title":"CESNET ipfixcol2 2.7.1 before 2.9.0 Memory Exhaustion via TCP LZ4 Decoder","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","status":"published","published":"2026-11-04T20:36:49.66Z","modified":"2026-11-07T07:02:55.28096503Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-789"],"updated_at":"2026-11-07T03:08:01.726202Z"},{"id":"DEBIAN-CVE-2026-122129","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","status":"published","published":"2026-11-04T21:18:08.38Z","modified":"2026-11-06T10:06:23.983029528Z","cvss":[{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"updated_at":"2026-11-06T10:38:22.758306Z"},{"id":"UBUNTU-CVE-2026-122129","description":"CESNET ipfixcol2 2.7.1 before 2.9.0 contains a memory allocation vulnerability in Lz4Decoder::read_start_header() that allows unauthenticated attackers to exhaust memory by declaring unbounded ring buffer sizes. Attackers can open TCP connections sending LZ4 start headers with very large buffer sizes, forcing up to 4 GiB allocations per connection and denying collector service.","status":"published","published":"2026-11-05T00:00:00Z","modified":"2026-11-06T01:00:41.983066501Z","cvss":[{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","level":"medium"},{"version":"4.0","score":6.9,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-06T01:33:05.666804Z"}]}}