{"id":"CVE-2021-33452","aliases":["AZL-41956","DEBIAN-CVE-2021-33452","EUVD-2021-20156","GHSA-fmxx-46x7-2phx","UBUNTU-CVE-2021-33452","USN-8248-1","USN-8248-2"],"status":"published","title":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in...","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","severity":{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary","from":"nvd"},"epss":{"day":"2026-11-10","score":0.00328,"percentile":0.261,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-401"],"published":"2022-07-26T12:36:18Z","modified":"2026-11-05T05:40:51Z","affected":[{"source":"osv","ecosystem":"Azure Linux:3","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"2.16.01-2"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.01-1","2.16.03-1","3.01-1"]},{"source":"osv","ecosystem":"Debian:13","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.03-1","3.01-1"]},{"source":"osv","ecosystem":"Debian:14","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.03-1","3.01-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.01-1","2.16.01-1build1","2.16.01-1ubuntu0.1~esm1","2.16.01-1ubuntu0.1~esm2"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.03-1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.15.05-1ubuntu0.1~esm1"}]}],"versions":["2.15.05-1"],"bundled":3},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.16.01-1ubuntu0.1~esm1"}]}],"versions":["2.16.01-1","2.16.01-1build1"],"bundled":3},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"nasm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.16.01-1ubuntu0.1~esm2"}]}],"versions":["2.16.01-1","2.16.01-1build1","2.16.01-1ubuntu0.1~esm1"],"bundled":2}],"products":[{"vendor":"nasm","product":"netwide_assembler"}],"references":[{"url":"https://bugzilla.nasm.us/show_bug.cgi?id=3392757","tags":["x_refsource_MISC","x_transferred","Exploit","Issue Tracking","Third Party Advisory","report"]},{"url":"https://gist.github.com/Clingto/bb632c0c463f4b2c97e4f65f751c5e6d","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-33452","tags":["web"]},{"url":"https://github.com/advisories/GHSA-fmxx-46x7-2phx"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-33452","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-33452","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-33452","tags":["report"]},{"url":"https://ubuntu.com/security/notices/USN-8248-1","tags":["advisory"]},{"url":"https://ubuntu.com/security/notices/USN-8248-2","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2021-33450","tags":["report"]},{"url":"https://ubuntu.com/security/CVE-2023-31722","tags":["report"]},{"url":"https://launchpad.net/bugs/2151861","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-33452","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-26T12:36:18Z","modified":"2024-08-03T23:50:42.376Z","updated_at":"2026-11-02T14:33:10.555814Z"}],"euvd":[{"id":"EUVD-2021-20156","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-26T12:36:18Z","modified":"2024-08-03T23:50:42Z","updated_at":"2026-11-03T03:24:34.304953Z"}],"ghsa":[{"id":"GHSA-fmxx-46x7-2phx","title":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in...","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-27T00:00:46Z","modified":"2023-01-27T05:07:26Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-401"],"updated_at":"2026-11-02T14:43:07.326529Z"}],"nvd":[{"id":"CVE-2021-33452","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-26T13:15:09.21Z","modified":"2026-06-17T03:54:34.63Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium","assessor":"primary"}],"cwes":["CWE-401"],"updated_at":"2026-11-02T14:07:06.501652Z"}],"osv":[{"id":"AZL-41956","title":"CVE-2021-33452 affecting package nasm 2.16.01-2","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-26T13:15:09Z","modified":"2026-11-05T05:40:51Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-05T16:41:19.893001Z"},{"id":"CVE-2021-33452","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-26T13:15:09.21Z","modified":"2026-03-14T10:59:19.075028Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:44:19.793849Z"},{"id":"DEBIAN-CVE-2021-33452","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-26T13:15:09.21Z","modified":"2026-10-23T18:03:14.716122395Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:45:35.233346Z"},{"id":"UBUNTU-CVE-2021-33452","description":"An issue was discovered in NASM version 2.16rc0. There are memory leaks in nasm_malloc() in nasmlib/alloc.c.","status":"published","published":"2022-07-26T13:15:00Z","modified":"2026-05-11T10:44:23.060610842Z","cvss":[{"version":"3.1","score":5.5,"vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:54:27.870979Z"},{"id":"USN-8248-1","title":"nasm vulnerabilities","description":"Daisy Chen discovered that NASM was vulnerable to a heap buffer overflow\nwhen handling certain input. An attacker could possibly use this issue\nto cause NASM to crash, resulting in a denial of service, or\npossibly execute arbitrary code. (CVE-2023-31722)\n\nIt was discovered that NASM incorrectly handled memory allocation.\nAn attacker could possibly use this issue to cause NASM to use\nexcessive resources, leading to a denial of service. This issue\nonly affected Ubuntu 24.04 LTS. (CVE-2021-33452, CVE-2021-33450)","status":"published","published":"2026-05-07T13:00:13Z","modified":"2026-05-11T10:46:46.739843Z","updated_at":"2026-11-02T16:58:22.951676Z"},{"id":"USN-8248-2","title":"nasm regression","description":"USN-8248-1 fixed vulnerabilities in NASM. Unfortunately the update\nintroduced a regression which could cause NASM to crash. This update fixes\nthe problem by reverting the fix for CVE-2021-33450 and CVE-2021-33452 in\nUbuntu 24.04 LTS.\n\nWe apologize for the inconvenience.\n\nOriginal advisory details:\n\n Daisy Chen discovered that NASM was vulnerable to a heap buffer overflow\n when handling certain input. An attacker could possibly use this issue  to\n cause NASM to crash, resulting in a denial of service, or  possibly\n execute arbitrary code. (CVE-2023-31722)\n\n It was discovered that NASM incorrectly handled memory allocation.  An\n attacker could possibly use this issue to cause NASM to use  excessive\n resources, leading to a denial of service. This issue  only affected\n Ubuntu 24.04 LTS. (CVE-2021-33452, CVE-2021-33450)","status":"published","published":"2026-05-08T14:22:34Z","modified":"2026-05-11T11:02:33.272843858Z","updated_at":"2026-11-02T16:58:22.951676Z"}]}}