CVE-2026-31528 (GCVE-0-2026-31528)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-08-05 12:23
VLAI
Title
perf: Make sure to use pmu_ctx->pmu for groups
Summary
In the Linux kernel, the following vulnerability has been resolved: perf: Make sure to use pmu_ctx->pmu for groups Oliver reported that x86_pmu_del() ended up doing an out-of-bound memory access when group_sched_in() fails and needs to roll back. This *should* be handled by the transaction callbacks, but he found that when the group leader is a software event, the transaction handlers of the wrong PMU are used. Despite the move_group case in perf_event_open() and group_sched_in() using pmu_ctx->pmu. Turns out, inherit uses event->pmu to clone the events, effectively undoing the move_group case for all inherited contexts. Fix this by also making inherit use pmu_ctx->pmu, ensuring all inherited counters end up in the same pmu context. Similarly, __perf_event_read() should use equally use pmu_ctx->pmu for the group case.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: bd27568117664b8b3e259721393df420ed51f57b , < 656f35b463995bee024d948440128230aacd81e1 (git)
Affected: bd27568117664b8b3e259721393df420ed51f57b , < 3a696e84a8b1fafdd774bb30d62919faf844d9e4 (git)
Affected: bd27568117664b8b3e259721393df420ed51f57b , < 35f7914e54fe7f13654c22ee045b05e4b6d8062b (git)
Affected: bd27568117664b8b3e259721393df420ed51f57b , < 4c759446046500a1a6785b25725725c3ff087ace (git)
Affected: bd27568117664b8b3e259721393df420ed51f57b , < 4b9ce671960627b2505b3f64742544ae9801df97 (git)
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Linux Linux Affected: 6.2
Unaffected: 0 , < 6.2 (semver)
Unaffected: 6.6.131 , ≤ 6.6.* (semver)
Unaffected: 6.12.80 , ≤ 6.12.* (semver)
Unaffected: 6.18.21 , ≤ 6.18.* (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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      "cve": "CVE-2026-31528",
      "id": "CVE-2026-31528",
      "initial_release_date": "2026-04-22T00:00:00+00:00",
      "product_status:known_affected": "260",
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      "source": "Red Hat CSAF VEX",
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      "title": "kernel: perf: Make sure to use pmu_ctx-\u003epmu for groups",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31528.json",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.