CVE-2026-64253 (GCVE-0-2026-64253)

Vulnerability from cvelistv5 – Published: 2026-07-24 15:31 – Updated: 2026-08-17 04:52
VLAI
Title
kernel/fork: clear PF_BLOCK_TS in copy_process()
Summary
In the Linux kernel, the following vulnerability has been resolved: kernel/fork: clear PF_BLOCK_TS in copy_process() PF_BLOCK_TS is only set in blk_time_get_ns() when current->plug is non-NULL, and blk_finish_plug() clears it via __blk_flush_plug() before NULLing the plug pointer. copy_process() breaks the invariant by inheriting PF_BLOCK_TS from the parent while resetting the child's plug to NULL. Clear PF_BLOCK_TS alongside that assignment so callers can rely on "PF_BLOCK_TS set implies current->plug != NULL" and dereference current->plug unguarded.
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < ee0801aceabdf583392477baf69a290b09448b8f (git)
Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < 99e6c712cc300883b8cbf03347d5359ec1a4d6dd (git)
Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < 77bba61a20f1b3d206f4f90e10a7bb3cd90b9619 (git)
Affected: 06b23f92af87a84d70881b2ecaa72e00f7838264 , < fd38b75c4b43295b10d69772a46d1c74dbd6fc81 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.9
Unaffected: 0 , < 6.9 (semver)
Unaffected: 6.12.95 , ≤ 6.12.* (semver)
Unaffected: 6.18.38 , ≤ 6.18.* (semver)
Unaffected: 7.1.3 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
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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.



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