{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80671","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-26T14:34:25.782Z","datePublished":"2026-08-28T06:49:11.744Z","dateUpdated":"2026-09-14T11:58:49.345Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-14T11:58:49.345Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nperf sched: Fix register_pid() overflow, strcpy, and BUG_ON\n\nregister_pid() has several issues when processing untrusted perf.data:\n\n1. Integer overflow: (pid + 1) * sizeof(struct task_desc *) can wrap\n   to a small value on 32-bit systems when pid is large (e.g.\n   0x40000000), causing realloc to return a tiny buffer followed by\n   out-of-bounds writes in the initialization loop.\n\n2. Heap buffer overflow: strcpy(task->comm, comm) copies the\n   untrusted comm string into a fixed 20-byte COMM_LEN buffer with\n   no length check.\n\n3. BUG_ON on allocation failure: perf.data is untrusted input, so\n   allocation failures should be handled gracefully rather than\n   killing the process.\n\n4. Realloc of sched->tasks assigned directly back, leaking the old\n   pointer on failure; nr_tasks incremented before the realloc,\n   leaving corrupted state on failure.\n\nCap pid at PID_MAX_LIMIT (4194304, matching the kernel's maximum\non 64-bit), replace strcpy with strlcpy, guard against NULL comm,\nreplace BUG_ON with NULL returns using safe realloc patterns, and\nadd NULL checks in callers that dereference the result."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","baseScore":9.3,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:L - The flaw is in userspace perf's builtin-sched.c reached only when a local user runs perf sched replay or perf sched latency against a crafted perf.data file via perf_session__process_events; it is not triggered by remote network packets, kernel syscalls, or in-kernel sched code.\nAC:L - The attacker fully controls untrusted perf.data sched_switch/sched_wakeup fields (prev_pid, next_pid, prev_comm, next_comm); large PIDs and overlong comm strings deterministically hit the integer-overflow realloc path or strcpy heap overflow without races or victim-specific memory layout.\nPR:N - In the malicious-trace threat model an external party needs no account or privileges on the victim host—they only supply a crafted perf.data file for a developer, support engineer, or CI job to analyze with perf sched replay/latency.\nUI:N - Once a trace is submitted to triage or CI, perf sched replay/latency parses perf.data non-interactively through perf_sched__read_events without further per-event operator actions beyond automated invocation of the perf command on the supplied file.\nS:C - Malicious sched metadata embedded in an externally supplied perf.data crosses from the untrusted reporter/artifact domain into the analyst or CI host security authority when perf parses that file, matching the kernel CNA untrusted-artifact model used for crafted filesystem images.\nC:H - Integer-overflow-driven out-of-bounds writes into the pid_to_task table and strcpy heap overflow past task_desc.comm[20] corrupt adjacent heap objects and can disclose process memory beyond a few bounded bytes.\nI:H - Attacker-controlled overflows corrupt task_desc function pointers and heap metadata (including the atoms pointer), providing controllable userspace memory corruption suitable for arbitrary write and code execution in the perf process.\nA:H - Pre-fix BUG_ON paths abort the perf process on allocation failure, and the heap out-of-bounds writes reliably crash or hang perf during register_pid() while parsing malicious perf.data."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["tools/perf/builtin-sched.c"],"versions":[{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"344e59fc4f2cba6dc04ce5e2a77388645d4ca834","status":"affected","versionType":"git"},{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"22263d241bad753217d545f8085b7ead52e2873b","status":"affected","versionType":"git"},{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"2003918e13f43cf6c5698be3cc9aa3657dd676a8","status":"affected","versionType":"git"},{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"29639f00bfa49da7904ba0a499e0da7a0e5d735e","status":"affected","versionType":"git"},{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"261d2b5f4afa0570ca906e553c93811c5abe4590","status":"affected","versionType":"git"},{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"652cea73b7b7b7c622a2be670e44e3c499c6d49f","status":"affected","versionType":"git"},{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"5ea1dcc9418c4e06ce29ed5170596f497ba86872","status":"affected","versionType":"git"},{"version":"ec156764d424dd67283c2cd5e9f6f1b8388364ac","lessThan":"5949d339f5ec98752d56dcd4e36f619a59d513a5","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["tools/perf/builtin-sched.c"],"versions":[{"version":"2.6.32","status":"affected"},{"version":"0","lessThan":"2.6.32","status":"unaffected","versionType":"semver"},{"version":"5.10.270","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.221","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.188","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.157","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.110","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.40","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.5","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","lessThanOrEqual":"*","status":"unaffected","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"5.10.270"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.32","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/344e59fc4f2cba6dc04ce5e2a77388645d4ca834"},{"url":"https://git.kernel.org/stable/c/22263d241bad753217d545f8085b7ead52e2873b"},{"url":"https://git.kernel.org/stable/c/2003918e13f43cf6c5698be3cc9aa3657dd676a8"},{"url":"https://git.kernel.org/stable/c/29639f00bfa49da7904ba0a499e0da7a0e5d735e"},{"url":"https://git.kernel.org/stable/c/261d2b5f4afa0570ca906e553c93811c5abe4590"},{"url":"https://git.kernel.org/stable/c/652cea73b7b7b7c622a2be670e44e3c499c6d49f"},{"url":"https://git.kernel.org/stable/c/5ea1dcc9418c4e06ce29ed5170596f497ba86872"},{"url":"https://git.kernel.org/stable/c/5949d339f5ec98752d56dcd4e36f619a59d513a5"}],"title":"perf sched: Fix register_pid() overflow, strcpy, and BUG_ON","x_generator":{"engine":"bippy-1.2.0"}}}}