CVE-2026-63968 (GCVE-0-2026-63968)

Vulnerability from cvelistv5 – Published: 2026-07-19 14:55 – Updated: 2026-07-20 13:41
VLAI
Title
ipv6: fix possible infinite loop in fib6_select_path()
Summary
In the Linux kernel, the following vulnerability has been resolved: ipv6: fix possible infinite loop in fib6_select_path() Found while auditing the same pattern Sashiko reported in rt6_fill_node() [1]. Apply the same fix as commit f8d8ce1b515a ("ipv6: fix possible infinite loop in fib6_info_uses_dev()"). Writers holding tb6_lock can list_del_rcu(&first->fib6_siblings) without waiting for RCU readers; first->fib6_siblings.next then still points into the old ring and this softirq-side walker never reaches &first->fib6_siblings as its terminator. fib6_purge_rt() always WRITE_ONCE()s first->fib6_nsiblings to 0 before list_del_rcu(), so an inside-loop check is a reliable detach signal. [1] https://sashiko.dev/#/patchset/20260526020227.4857-1-jiayuan.chen%40linux.dev
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: d0ec61c9f3583b76aebdbb271f5c0d3fcccd48b2 , < 3948a7d92f7678e89e1776bb2d169afcad63b1ae (git)
Affected: 52da02521ede55fb86546c3fffd9377b3261b91f , < c87cd3cb309634bc8f50a54e2079424f219ac21f (git)
Affected: 34a949e7a0869dfa31a40416d2a56973fae1807b , < 0f7b73c3452635de83b8711b31abdda8e49aad7b (git)
Affected: d9ccb18f83ea2bb654289b6ecf014fd267cc988b , < ab9a10969a907b472a0196d999c08ff7144172e3 (git)
Affected: d9ccb18f83ea2bb654289b6ecf014fd267cc988b , < 9b9d5bd6e3d4c9cecab5407604b690684b2532d2 (git)
Affected: d9ccb18f83ea2bb654289b6ecf014fd267cc988b , < 9c7da87c2dc860bb17ca1ece942495d28b1ce3b9 (git)
Affected: 11edcd026012ac18acee0f1514db3ed1b160fc6f (git)
Affected: 6.1.128 , < 6.1.176 (semver)
Affected: 6.6.75 , < 6.6.143 (semver)
Affected: 6.12.2 , < 6.12.93 (semver)
Affected: 6.11.11 , < 6.12 (semver)
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Linux Linux Affected: 6.13
Unaffected: 0 , < 6.13 (semver)
Unaffected: 6.1.176 , ≤ 6.1.* (semver)
Unaffected: 6.6.143 , ≤ 6.6.* (semver)
Unaffected: 6.12.93 , ≤ 6.12.* (semver)
Unaffected: 6.18.35 , ≤ 6.18.* (semver)
Unaffected: 7.0.12 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (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.


Detection rules are retrieved from Rulezet.