CVE-2026-52933 (GCVE-0-2026-52933)

Vulnerability from cvelistv5 – Published: 2026-06-24 07:14 – Updated: 2026-06-28 06:36
VLAI
Title
io_uring/poll: fix signed comparison in io_poll_get_ownership()
Summary
In the Linux kernel, the following vulnerability has been resolved: io_uring/poll: fix signed comparison in io_poll_get_ownership() io_poll_get_ownership() uses a signed comparison to check whether poll_refs has reached the threshold for the slowpath: if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS)) atomic_read() returns int (signed). When IO_POLL_CANCEL_FLAG (BIT(31)) is set in poll_refs, the value becomes negative in signed arithmetic, so the >= 128 comparison always evaluates to false and the slowpath is never taken. Fix this by casting the atomic_read() result to unsigned int before the comparison, so that the cancel flag is treated as a large positive value and correctly triggers the slowpath.
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
Linux Linux Affected: a26a35e9019fd70bf3cf647dcfdae87abc7bacea , < 81bf96b0abbfa4cd47ea32e12596aed3855fb2f3 (git)
Affected: a26a35e9019fd70bf3cf647dcfdae87abc7bacea , < cf522703d4f194991615763697ae25a3f9539763 (git)
Affected: a26a35e9019fd70bf3cf647dcfdae87abc7bacea , < fc47043f3d9af3efa407665b47f8378ec691ba18 (git)
Affected: a26a35e9019fd70bf3cf647dcfdae87abc7bacea , < ea0697129807d718037f618221037aa0660ee3c5 (git)
Affected: a26a35e9019fd70bf3cf647dcfdae87abc7bacea , < c6d191164dc81838d8dbf452a6000f68c558d1ae (git)
Affected: a26a35e9019fd70bf3cf647dcfdae87abc7bacea , < 326941b22806cbf2df1fbfe902b7908b368cce42 (git)
Affected: 4b702b7d11ce1b9d26fc6d7c5a7ef4ac1d455048 (git)
Affected: bc4e6ee16778149811333a969a7a893d4cc110c5 (git)
Affected: 5.15.82 , < 5.16 (semver)
Affected: 6.0.11 , < 6.1 (semver)
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Linux Linux Affected: 6.1
Unaffected: 0 , < 6.1 (semver)
Unaffected: 6.1.175 , ≤ 6.1.* (semver)
Unaffected: 6.6.140 , ≤ 6.6.* (semver)
Unaffected: 6.12.86 , ≤ 6.12.* (semver)
Unaffected: 6.18.27 , ≤ 6.18.* (semver)
Unaffected: 7.0.4 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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When IO_POLL_CANCEL_FLAG\\n(BIT(31)) is set in poll_refs, the value becomes negative in\\nsigned arithmetic, so the \u003e= 128 comparison always evaluates to\\nfalse and the slowpath is never taken.\\n\\nFix this by casting the atomic_read() result to unsigned int\\nbefore the comparison, so that the cancel flag is treated as a\\nlarge positive value and correctly triggers the slowpath.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"io_uring/poll.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"a26a35e9019fd70bf3cf647dcfdae87abc7bacea\",\"lessThan\":\"81bf96b0abbfa4cd47ea32e12596aed3855fb2f3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a26a35e9019fd70bf3cf647dcfdae87abc7bacea\",\"lessThan\":\"cf522703d4f194991615763697ae25a3f9539763\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a26a35e9019fd70bf3cf647dcfdae87abc7bacea\",\"lessThan\":\"fc47043f3d9af3efa407665b47f8378ec691ba18\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a26a35e9019fd70bf3cf647dcfdae87abc7bacea\",\"lessThan\":\"ea0697129807d718037f618221037aa0660ee3c5\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a26a35e9019fd70bf3cf647dcfdae87abc7bacea\",\"lessThan\":\"c6d191164dc81838d8dbf452a6000f68c558d1ae\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"a26a35e9019fd70bf3cf647dcfdae87abc7bacea\",\"lessThan\":\"326941b22806cbf2df1fbfe902b7908b368cce42\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"4b702b7d11ce1b9d26fc6d7c5a7ef4ac1d455048\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"bc4e6ee16778149811333a969a7a893d4cc110c5\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"5.15.82\",\"lessThan\":\"5.16\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.0.11\",\"lessThan\":\"6.1\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"io_uring/poll.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"6.1\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"6.1\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.175\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.140\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.86\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.27\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.0.4\",\"lessThanOrEqual\":\"7.0.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{\"cvssMetricV31\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"type\":\"Secondary\",\"cvssData\":{\"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\",\"attackVector\":\"LOCAL\",\"attackComplexity\":\"LOW\",\"privilegesRequired\":\"LOW\",\"userInteraction\":\"NONE\",\"scope\":\"UNCHANGED\",\"confidentialityImpact\":\"HIGH\",\"integrityImpact\":\"HIGH\",\"availabilityImpact\":\"HIGH\"},\"exploitabilityScore\":1.8,\"impactScore\":5.9}]},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/326941b22806cbf2df1fbfe902b7908b368cce42\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/81bf96b0abbfa4cd47ea32e12596aed3855fb2f3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/c6d191164dc81838d8dbf452a6000f68c558d1ae\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/cf522703d4f194991615763697ae25a3f9539763\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ea0697129807d718037f618221037aa0660ee3c5\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/fc47043f3d9af3efa407665b47f8378ec691ba18\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}"
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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.