{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-31528", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-03-09T15:48:24.111Z", "datePublished": "2026-04-22T13:54:41.180Z", "dateUpdated": "2026-08-05T12:23:18.524Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:23:18.524Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nperf: Make sure to use pmu_ctx->pmu for groups\n\nOliver reported that x86_pmu_del() ended up doing an out-of-bound memory access\nwhen group_sched_in() fails and needs to roll back.\n\nThis *should* be handled by the transaction callbacks, but he found that when\nthe group leader is a software event, the transaction handlers of the wrong PMU\nare used. Despite the move_group case in perf_event_open() and group_sched_in()\nusing pmu_ctx->pmu.\n\nTurns out, inherit uses event->pmu to clone the events, effectively undoing the\nmove_group case for all inherited contexts. Fix this by also making inherit use\npmu_ctx->pmu, ensuring all inherited counters end up in the same pmu context.\n\nSimilarly, __perf_event_read() should use equally use pmu_ctx->pmu for the\ngroup case." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The vulnerable perf group/inheritance paths are reached through the local perf_event_open syscall and subsequent fork/scheduling/read operations, not by network or physical input.\nAC:L - An attacker controls the perf event group composition, inherit flag, fork, and can create an over-constrained hardware group to force group_sched_in rollback; no uncontrollable race is required.\nPR:L - A normal unprivileged local user can create per-process user-space perf events under the default perf_event_paranoid=2 policy by excluding kernel profiling, so real administrative privileges are not required.\nUI:N - The attacker can trigger the sequence entirely from their own process using perf_event_open and fork/read/scheduling activity without any victim action.\nS:U - The bug corrupts kernel perf/PMU bookkeeping within the same kernel security authority and does not cross a VM, IOMMU, or other separate security boundary.\nC:H - The reported out-of-bounds access occurs in kernel PMU bookkeeping and includes memory corruption in per-CPU structures; per the higher-severity rule, this can reasonably be leveraged for kernel information disclosure.\nI:H - The rollback path can drive x86_pmu_del with inconsistent PMU transaction state, causing out-of-bounds writes such as invalid PMU array/bitmap updates, which is kernel memory corruption with potential control-flow or privilege impact.\nA:H - Even without full exploitation, the out-of-bounds kernel access can reliably produce a kernel warning/oops/panic or corrupt PMU state, causing high availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/events/core.c" ], "versions": [ { "version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "656f35b463995bee024d948440128230aacd81e1", "status": "affected", "versionType": "git" }, { "version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "3a696e84a8b1fafdd774bb30d62919faf844d9e4", "status": "affected", "versionType": "git" }, { "version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "35f7914e54fe7f13654c22ee045b05e4b6d8062b", "status": "affected", "versionType": "git" }, { "version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "4c759446046500a1a6785b25725725c3ff087ace", "status": "affected", "versionType": "git" }, { "version": "bd27568117664b8b3e259721393df420ed51f57b", "lessThan": "4b9ce671960627b2505b3f64742544ae9801df97", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "kernel/events/core.c" ], "versions": [ { "version": "6.2", "status": "affected" }, { "version": "0", "lessThan": "6.2", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.131", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.80", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.21", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.11", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "6.2", "versionEndExcluding": "6.6.131" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.12.80" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.18.21" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.19.11" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/656f35b463995bee024d948440128230aacd81e1" }, { "url": "https://git.kernel.org/stable/c/3a696e84a8b1fafdd774bb30d62919faf844d9e4" }, { "url": "https://git.kernel.org/stable/c/35f7914e54fe7f13654c22ee045b05e4b6d8062b" }, { "url": "https://git.kernel.org/stable/c/4c759446046500a1a6785b25725725c3ff087ace" }, { "url": "https://git.kernel.org/stable/c/4b9ce671960627b2505b3f64742544ae9801df97" } ], "title": "perf: Make sure to use pmu_ctx->pmu for groups", "x_generator": { "engine": "bippy-1.2.0" } } } }