CVE-2025-21759 (GCVE-0-2025-21759)

Vulnerability from cvelistv5 – Published: 2025-02-27 02:18 – Updated: 2026-05-11 21:05
VLAI
Title
ipv6: mcast: extend RCU protection in igmp6_send()
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: mcast: extend RCU protection in igmp6_send() igmp6_send() can be called without RTNL or RCU being held. Extend RCU protection so that we can safely fetch the net pointer and avoid a potential UAF. Note that we no longer can use sock_alloc_send_skb() because ipv6.igmp_sk uses GFP_KERNEL allocations which can sleep. Instead use alloc_skb() and charge the net->ipv6.igmp_sk socket under RCU protection.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 , < 81b25a07ebf53f9ef4ca8f3d96a8ddb94561dd5a (git)
Affected: b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 , < 0bf8e2f3768629d437a32cb824149e6e98254381 (git)
Affected: b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 , < 8e92d6a413feaf968a33f0b439ecf27404407458 (git)
Affected: b8ad0cbc58f703972e9e37c4e2a8081dd7e6a551 , < 087c1faa594fa07a66933d750c0b2610aa1a2946 (git)
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Linux Linux Affected: 2.6.26
Unaffected: 0 , < 2.6.26 (semver)
Unaffected: 6.6.79 , ≤ 6.6.* (semver)
Unaffected: 6.12.16 , ≤ 6.12.* (semver)
Unaffected: 6.13.4 , ≤ 6.13.* (semver)
Unaffected: 6.14 , ≤ * (original_commit_for_fix)
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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.