{"id":"CVE-2023-53221","state":"PUBLISHED","title":"bpf: Fix memleak due to fentry attach failure","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix memleak due to fentry attach failure\n\nIf it fails to attach fentry, the allocated bpf trampoline image will be\nleft in the system. That can be verified by checking /proc/kallsyms.\n\nThis meamleak can be verified by a simple bpf program as follows:\n\n  SEC(\"fentry/trap_init\")\n  int fentry_run()\n  {\n      return 0;\n  }\n\nIt will fail to attach trap_init because this function is freed after\nkernel init, and then we can find the trampoline image is left in the\nsystem by checking /proc/kallsyms.\n\n  $ tail /proc/kallsyms\n  ffffffffc0613000 t bpf_trampoline_6442453466_1  [bpf]\n  ffffffffc06c3000 t bpf_trampoline_6442453466_1  [bpf]\n\n  $ bpftool btf dump file /sys/kernel/btf/vmlinux | grep \"FUNC 'trap_init'\"\n  [2522] FUNC 'trap_init' type_id=119 linkage=static\n\n  $ echo $((6442453466 & 0x7fffffff))\n  2522\n\nNote that there are two left bpf trampoline images, that is because the\nlibbpf will fallback to raw tracepoint if -EINVAL is returned.","publishedAt":"2025-09-15T14:21:50.053Z","updatedAt":"2026-05-23T15:28:16.750Z","severity":{"score":5.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","source":"CISA-ADP"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"20109ddd5bea2c24d790debf5d02584ef24c3f5e","versionType":"git"},{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"f72c67d1a82dada7d6d504c806e111e913721a30","versionType":"git"},{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"6aa27775db63ba8c7c73891c7dfb71ddc230c48d","versionType":"git"},{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"108598c39eefbedc9882273ac0df96127a629220","versionType":"git"},{"version":"e21d2b92354b3cd25dd774ebb0f0e52ff04a7861","status":"affected","versionType":"git"},{"version":"85d177f56e5256e14b74a65940f981f6e3e8bb32","status":"affected","versionType":"git"},{"version":"5.10.28","status":"affected","lessThan":"5.11","versionType":"semver"},{"version":"5.11.11","status":"affected","lessThan":"5.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/trampoline.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","versionType":"semver"},{"version":"6.1.39","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.3.13","status":"unaffected","lessThanOrEqual":"6.3.*","versionType":"semver"},{"version":"6.4.4","status":"unaffected","lessThanOrEqual":"6.4.*","versionType":"semver"},{"version":"6.5","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/trampoline.c"]}],"references":["https://git.kernel.org/stable/c/20109ddd5bea2c24d790debf5d02584ef24c3f5e","https://git.kernel.org/stable/c/f72c67d1a82dada7d6d504c806e111e913721a30","https://git.kernel.org/stable/c/6aa27775db63ba8c7c73891c7dfb71ddc230c48d","https://git.kernel.org/stable/c/108598c39eefbedc9882273ac0df96127a629220"],"weaknesses":["CWE-401"],"ingestedAt":"2026-10-29T20:06:33.064Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2023/53xxx/CVE-2023-53221.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-53221","state":"PUBLISHED","datePublished":"2025-09-15T14:21:50.053Z","dateUpdated":"2026-05-23T15:28:16.750Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-09-15T14:19:21.845Z"},"containers":{"cna":{"title":"bpf: Fix memleak due to fentry attach failure","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Fix memleak due to fentry attach failure\n\nIf it fails to attach fentry, the allocated bpf trampoline image will be\nleft in the system. That can be verified by checking /proc/kallsyms.\n\nThis meamleak can be verified by a simple bpf program as follows:\n\n  SEC(\"fentry/trap_init\")\n  int fentry_run()\n  {\n      return 0;\n  }\n\nIt will fail to attach trap_init because this function is freed after\nkernel init, and then we can find the trampoline image is left in the\nsystem by checking /proc/kallsyms.\n\n  $ tail /proc/kallsyms\n  ffffffffc0613000 t bpf_trampoline_6442453466_1  [bpf]\n  ffffffffc06c3000 t bpf_trampoline_6442453466_1  [bpf]\n\n  $ bpftool btf dump file /sys/kernel/btf/vmlinux | grep \"FUNC 'trap_init'\"\n  [2522] FUNC 'trap_init' type_id=119 linkage=static\n\n  $ echo $((6442453466 & 0x7fffffff))\n  2522\n\nNote that there are two left bpf trampoline images, that is because the\nlibbpf will fallback to raw tracepoint if -EINVAL is returned."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"20109ddd5bea2c24d790debf5d02584ef24c3f5e","versionType":"git"},{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"f72c67d1a82dada7d6d504c806e111e913721a30","versionType":"git"},{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"6aa27775db63ba8c7c73891c7dfb71ddc230c48d","versionType":"git"},{"version":"e21aa341785c679dd409c8cb71f864c00fe6c463","status":"affected","lessThan":"108598c39eefbedc9882273ac0df96127a629220","versionType":"git"},{"version":"e21d2b92354b3cd25dd774ebb0f0e52ff04a7861","status":"affected","versionType":"git"},{"version":"85d177f56e5256e14b74a65940f981f6e3e8bb32","status":"affected","versionType":"git"},{"version":"5.10.28","status":"affected","lessThan":"5.11","versionType":"semver"},{"version":"5.11.11","status":"affected","lessThan":"5.12","versionType":"semver"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/trampoline.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.12","versionType":"semver"},{"version":"6.1.39","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.3.13","status":"unaffected","lessThanOrEqual":"6.3.*","versionType":"semver"},{"version":"6.4.4","status":"unaffected","lessThanOrEqual":"6.4.*","versionType":"semver"},{"version":"6.5","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["kernel/bpf/trampoline.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/20109ddd5bea2c24d790debf5d02584ef24c3f5e"},{"url":"https://git.kernel.org/stable/c/f72c67d1a82dada7d6d504c806e111e913721a30"},{"url":"https://git.kernel.org/stable/c/6aa27775db63ba8c7c73891c7dfb71ddc230c48d"},{"url":"https://git.kernel.org/stable/c/108598c39eefbedc9882273ac0df96127a629220"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-23T15:28:16.750Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.1.39"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.3.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.4.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.12","versionEndExcluding":"6.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.10.28"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.11.11"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":5.5,"attackVector":"LOCAL","baseSeverity":"MEDIUM","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"LOW","confidentialityImpact":"NONE"}},{"other":{"type":"ssvc","content":{"id":"CVE-2023-53221","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-01-14T17:50:19.613865Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-401","lang":"en","type":"CWE","description":"CWE-401 Missing Release of Memory after Effective Lifetime"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-01-14T17:52:59.043Z"}}]}}}