CVE-2026-74581
net: ipv6: clear suppressed fib6 rule result
Description
In the Linux kernel, the following vulnerability has been resolved: net: ipv6: clear suppressed fib6 rule result fib6_rule_suppress() drops a suppressed route with ip6_rt_put_flags(), but leaves res->rt6 pointing at the released rt6_info. If no later rule supplies a replacement, fib6_rule_lookup() still sees res.rt6 and returns that stale dst to its caller. A suppressing rule can therefore leak a released route back to rt6_lookup(), and the next put hits rcuref_put_slowpath() from dst_release(). Clear res->rt6 when suppressing the route so suppressed lookups fall through to the null dst instead of reusing the released one.
INFO
Published Date :
Aug. 21, 2026, 5:16 p.m.
Last Modified :
Oct. 16, 2026, 8:17 p.m.
Remotely Exploit :
Yes !
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Clear route pointer in fib6_rule_suppress.
- Ensure lookups fall through to null destination.
- Apply kernel patches for ipv6 routing.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-74581.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74581 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-74581
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-74581 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74581 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Oct. 16, 2026
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/354db6243eca59e9d187ffbf8b7955b044ce84dc Added Reference https://git.kernel.org/stable/c/5d29b286c9de0b309e94b9ed083aa1a2f429434f Added Reference https://git.kernel.org/stable/c/6aea62e433fe1b586202a5fee8b5807ce635e1d7 Added Reference https://git.kernel.org/stable/c/6d98c70fe0ba8c7708bfd5b2a5174d2086775daa Added Reference https://git.kernel.org/stable/c/90c57310e266eb94e4a80d6b15a9ca131d2e82cb Added Reference https://git.kernel.org/stable/c/9bad152c42b37499162367fe47867411e62fffa3 Added Reference https://git.kernel.org/stable/c/a341c091ca0bfae377747b1b59a3bd8ebe18a937 Added Reference https://git.kernel.org/stable/c/dc3ab04220667f254f4348572b2a0b3febff89fb Removed Reference https://git.kernel.org/stable/c/354db6243eca59e9d187ffbf8b7955b044ce84dc Removed Reference https://git.kernel.org/stable/c/5d29b286c9de0b309e94b9ed083aa1a2f429434f Removed Reference https://git.kernel.org/stable/c/6aea62e433fe1b586202a5fee8b5807ce635e1d7 Removed Reference https://git.kernel.org/stable/c/6d98c70fe0ba8c7708bfd5b2a5174d2086775daa Removed Reference https://git.kernel.org/stable/c/90c57310e266eb94e4a80d6b15a9ca131d2e82cb Removed Reference https://git.kernel.org/stable/c/9bad152c42b37499162367fe47867411e62fffa3 Removed Reference https://git.kernel.org/stable/c/a341c091ca0bfae377747b1b59a3bd8ebe18a937 Removed Reference https://git.kernel.org/stable/c/dc3ab04220667f254f4348572b2a0b3febff89fb -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Oct. 16, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-74581', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-10-16T19:01:10.675016Z'} -
CVE Translated by [email protected]
Oct. 14, 2026
Action Type Old Value New Value Added Translation Title: Linux, Description: En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: red: ipv6: limpiar resultado de regla fib6 suprimida fib6_rule_suppress() descarta una ruta suprimida con ip6_rt_put_flags(), pero deja res -> rt6 apuntando a la rt6_info liberada. Si ninguna regla posterior proporciona un reemplazo, fib6_rule_lookup() todavía ve res.rt6 y devuelve ese dst obsoleto a su llamador. Una regla de supresión puede, por lo tanto, filtrar una ruta liberada de vuelta a rt6_lookup(), y el siguiente put alcanza rcuref_put_slowpath() desde dst_release(). Limpiar res -> rt6 al suprimir la ruta para que las búsquedas suprimidas pasen al dst nulo en lugar de reutilizar el liberado. -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 25, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 21, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '209d35ee34e25f9668c404350a1c86d914c54ffa', 'lessThan': '90c57310e266eb94e4a80d6b15a9ca131d2e82cb', 'versionType': 'git'}, {'status': 'affected', 'version': '8ef8a76a340ebdb2c2eea3f6fb0ebbed09a16383', 'lessThan': '5d29b286c9de0b309e94b9ed083aa1a2f429434f', 'versionType': 'git'}, {'status': 'affected', 'version': 'cdef485217d30382f3bf6448c54b4401648fe3f1', 'lessThan': '354db6243eca59e9d187ffbf8b7955b044ce84dc', 'versionType': 'git'}, {'status': 'affected', 'version': 'cdef485217d30382f3bf6448c54b4401648fe3f1', 'lessThan': '6d98c70fe0ba8c7708bfd5b2a5174d2086775daa', 'versionType': 'git'}, {'status': 'affected', 'version': 'cdef485217d30382f3bf6448c54b4401648fe3f1', 'lessThan': '9bad152c42b37499162367fe47867411e62fffa3', 'versionType': 'git'}, {'status': 'affected', 'version': 'cdef485217d30382f3bf6448c54b4401648fe3f1', 'lessThan': 'dc3ab04220667f254f4348572b2a0b3febff89fb', 'versionType': 'git'}, {'status': 'affected', 'version': 'cdef485217d30382f3bf6448c54b4401648fe3f1', 'lessThan': 'a341c091ca0bfae377747b1b59a3bd8ebe18a937', 'versionType': 'git'}, {'status': 'affected', 'version': 'cdef485217d30382f3bf6448c54b4401648fe3f1', 'lessThan': '6aea62e433fe1b586202a5fee8b5807ce635e1d7', 'versionType': 'git'}, {'status': 'affected', 'version': 'ee38eb8cf9a7323884c2b8e0adbbeb2192d31e29', 'versionType': 'git'}, {'status': 'affected', 'version': '5.10.84', 'lessThan': '5.10.265', 'versionType': 'semver'}, {'status': 'affected', 'version': '5.15.7', 'lessThan': '5.15.216', 'versionType': 'semver'}, {'status': 'affected', 'version': '5.4.164', 'lessThan': '5.5', 'versionType': 'semver'}], 'programFiles': ['net/ipv6/fib6_rules.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '5.16'}, {'status': 'unaffected', 'version': '0', 'lessThan': '5.16', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '5.10.265', 'versionType': 'semver', 'lessThanOrEqual': '5.10.*'}, {'status': 'unaffected', 'version': '5.15.216', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.183', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.151', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.103', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.44', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.8', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['net/ipv6/fib6_rules.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: net: ipv6: clear suppressed fib6 rule result fib6_rule_suppress() drops a suppressed route with ip6_rt_put_flags(), but leaves res->rt6 pointing at the released rt6_info. If no later rule supplies a replacement, fib6_rule_lookup() still sees res.rt6 and returns that stale dst to its caller. A suppressing rule can therefore leak a released route back to rt6_lookup(), and the next put hits rcuref_put_slowpath() from dst_release(). Clear res->rt6 when suppressing the route so suppressed lookups fall through to the null dst instead of reusing the released one. Added Reference https://git.kernel.org/stable/c/354db6243eca59e9d187ffbf8b7955b044ce84dc Added Reference https://git.kernel.org/stable/c/5d29b286c9de0b309e94b9ed083aa1a2f429434f Added Reference https://git.kernel.org/stable/c/6aea62e433fe1b586202a5fee8b5807ce635e1d7 Added Reference https://git.kernel.org/stable/c/6d98c70fe0ba8c7708bfd5b2a5174d2086775daa Added Reference https://git.kernel.org/stable/c/90c57310e266eb94e4a80d6b15a9ca131d2e82cb Added Reference https://git.kernel.org/stable/c/9bad152c42b37499162367fe47867411e62fffa3 Added Reference https://git.kernel.org/stable/c/a341c091ca0bfae377747b1b59a3bd8ebe18a937 Added Reference https://git.kernel.org/stable/c/dc3ab04220667f254f4348572b2a0b3febff89fb