CVE-2026-31516 (GCVE-0-2026-31516)

Vulnerability from cvelistv5 – Published: 2026-04-22 13:54 – Updated: 2026-08-05 12:23
VLAI
Title
xfrm: prevent policy_hthresh.work from racing with netns teardown
Summary
In the Linux kernel, the following vulnerability has been resolved: xfrm: prevent policy_hthresh.work from racing with netns teardown A XFRM_MSG_NEWSPDINFO request can queue the per-net work item policy_hthresh.work onto the system workqueue. The queued callback, xfrm_hash_rebuild(), retrieves the enclosing struct net via container_of(). If the net namespace is torn down before that work runs, the associated struct net may already have been freed, and xfrm_hash_rebuild() may then dereference stale memory. xfrm_policy_fini() already flushes policy_hash_work during teardown, but it does not synchronize policy_hthresh.work. Synchronize policy_hthresh.work in xfrm_policy_fini() as well, so the queued work cannot outlive the net namespace teardown and access a freed struct net.
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: 880a6fab8f6ba5b5abe59ea68533202ddea1012c , < 56ea2257b83ee29a543f158159e3d1abc1e3e4fe (git)
Affected: 880a6fab8f6ba5b5abe59ea68533202ddea1012c , < 8854e9367465d784046362698731c1111e3b39b8 (git)
Affected: 880a6fab8f6ba5b5abe59ea68533202ddea1012c , < 4e2e77843fef473ef47e322d52436d8308582a96 (git)
Affected: 880a6fab8f6ba5b5abe59ea68533202ddea1012c , < 29fe3a61bcdce398ee3955101c39f89c01a8a77e (git)
guessed Create a notification for this product.
Linux Linux Affected: 3.18
Unaffected: 0 , < 3.18 (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)
guessed Create a notification for this product.
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      "title": "kernel: xfrm: prevent policy_hthresh.work from racing with netns teardown",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31516.json",
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}



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