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Fencer Vulns
high 7.8

CVE-2022-48950 json

perf: Fix perf_pending_task() UaF

published 2024-10-21 2 y ago modified 2026-08-05 3 mo ago also EUVD-2022-53829

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 16%
public exploits
0
none known

Summary

In the Linux kernel, the following vulnerability has been resolved:

perf: Fix perf_pending_task() UaF

Per syzbot it is possible for perf_pending_task() to run after the event is free()'d. There are two related but distinct cases:

- the task_work was already queued before destroying the event; - destroying the event itself queues the task_work.

The first cannot be solved using task_work_cancel() since perf_release() itself might be called from a task_work (____fput), which means the current->task_works list is already empty and task_work_cancel() won't be able to find the perf_pending_task() entry.

The simplest alternative is extending the perf_event lifetime to cover the task_work.

The second is just silly, queueing a task_work while you know the event is going away makes no sense and is easily avoided by re-arranging how the event is marked STATE_DEAD and ensuring it goes through STATE_OFF on the way down.

Patch / fix

  • Linux Linux 5.15.84, 6.0.14
  • linux Debian 14, Debian 13, Debian 12 6.1.4-1

debian advisories DEBIAN-CVE-2022-48950

  • linux Ubuntu 22.04 LTS 5.15.0-67.74
  • linux-aws Ubuntu 22.04 LTS 5.15.0-1031.35
  • linux-gcp Ubuntu 22.04 LTS 5.15.0-1030.37
  • linux-gke Ubuntu 22.04 LTS 5.15.0-1028.33
  • linux-ibm Ubuntu 22.04 LTS 5.15.0-1026.29
  • linux-kvm Ubuntu 22.04 LTS 5.15.0-1029.34
  • linux-azure Ubuntu 22.04 LTS 5.15.0-1034.41
  • linux-gkeop Ubuntu 22.04 LTS 5.15.0-1016.21

ubuntu advisories UBUNTU-CVE-2022-48950

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel RHEL 9 5.14.0-362.8.1.el9_3
  • rv RHEL 9 5.14.0-362.8.1.el9_3
  • perf RHEL 9 5.14.0-362.8.1.el9_3
  • rtla RHEL 9 5.14.0-362.8.1.el9_3
  • bpftool RHEL 9 7.2.0-362.8.1.el9_3
  • libperf RHEL 9 5.14.0-362.8.1.el9_3
  • kernel-rt RHEL 9 5.14.0-362.8.1.el9_3
  • kernel-64k RHEL 9 5.14.0-362.8.1.el9_3

red hat advisories RHSA-2023:6583

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2022-48950 updated cvss 6.7

kernel: perf: Fix perf_pending_task() UaF

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more
    affected: workaround, no fix planned “Out of support scope”
  • Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-core, kernel-tools, python3-perf, +17 more
    affected: workaround, no fix planned “Will not fix”
  • Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more
    affected: workaround, no fix available
  • Red Hat Enterprise Linux 8 kernel-rt, kernel-rt-kvm, kernel-rt-core, kernel-rt-modules, kernel-rt-debug-kvm, kernel-rt-debug-core, +6 more
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2 y ago

Exploit prediction

0.25% chance of exploitation in the next 30 days, higher than 16% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Linux Linux

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.