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CVE-2026-74344 (GCVE-0-2026-74344)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:58 – Updated: 2026-08-17 05:46
VLAI
Title
bpf: Clear rb node linkage when freeing bpf_rb_root
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Clear rb node linkage when freeing bpf_rb_root bpf_rb_root_free() detaches the root by copying the current rb_root_cached and then replacing the live root with RB_ROOT_CACHED. It then walks the copied root and drops each object contained in the tree. This leaves the rb node state intact while dropping the object. If the object is refcounted and survives the drop, its bpf_rb_node_kern still contains an owner pointer to the freed root and stale rb tree linkage. If a later bpf_rb_root allocation reuses the same address, bpf_rbtree_remove() can incorrectly pass the owner check and call rb_erase_cached() on a node whose rb pointers belong to the old tree. Mirror the list draining behavior by marking nodes as busy while the root is being detached, then clear the rb node and release the owner before dropping the containing object. This makes surviving nodes unowned and safe to reject from remove or accept for a later add.
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: 9c395c1b99bd23f74bc628fa000480c49593d17f , < 2eb39de4962f842d653e96818ae372665cd481fd (git)
Affected: 9c395c1b99bd23f74bc628fa000480c49593d17f , < 574612793bed416f6c05fe7c9b50e9eb0441997e (git)
Affected: 9c395c1b99bd23f74bc628fa000480c49593d17f , < 4a7910ee060d8ce55612f5b3cc267f3a265a3cec (git)
Affected: 1d0675957d35ac5e514073481beda62e4e1e2ec5 (git)
Affected: 6.2.15 , < 6.3 (semver)
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Linux Linux Affected: 6.3
Unaffected: 0 , < 6.3 (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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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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