CVE-2026-74581

Summary

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.

Affected Software

VendorProductVersion RangeStatus
LinuxLinux209d35ee34e25f9668c404350a1c86d914c54ffa < 90c57310e266eb94e4a80d6b15a9ca131d2e82cbaffected
LinuxLinux8ef8a76a340ebdb2c2eea3f6fb0ebbed09a16383 < 5d29b286c9de0b309e94b9ed083aa1a2f429434faffected
LinuxLinuxcdef485217d30382f3bf6448c54b4401648fe3f1 < 354db6243eca59e9d187ffbf8b7955b044ce84dcaffected
LinuxLinuxcdef485217d30382f3bf6448c54b4401648fe3f1 < 6d98c70fe0ba8c7708bfd5b2a5174d2086775daaaffected
LinuxLinuxcdef485217d30382f3bf6448c54b4401648fe3f1 < 9bad152c42b37499162367fe47867411e62fffa3affected
LinuxLinuxcdef485217d30382f3bf6448c54b4401648fe3f1 < dc3ab04220667f254f4348572b2a0b3febff89fbaffected
LinuxLinuxcdef485217d30382f3bf6448c54b4401648fe3f1 < a341c091ca0bfae377747b1b59a3bd8ebe18a937affected
LinuxLinuxcdef485217d30382f3bf6448c54b4401648fe3f1 < 6aea62e433fe1b586202a5fee8b5807ce635e1d7affected
LinuxLinuxee38eb8cf9a7323884c2b8e0adbbeb2192d31e29affected
LinuxLinux5.10.84 < 5.10.265affected
LinuxLinux5.15.7 < 5.15.216affected
LinuxLinux5.4.164 < 5.5affected
LinuxLinux5.16affected
LinuxLinux0 < 5.16unaffected
LinuxLinux5.10.265 <= 5.10.*unaffected
LinuxLinux5.15.216 <= 5.15.*unaffected
LinuxLinux6.1.183 <= 6.1.*unaffected
LinuxLinux6.6.151 <= 6.6.*unaffected
LinuxLinux6.12.103 <= 6.12.*unaffected
LinuxLinux6.18.44 <= 6.18.*unaffected
LinuxLinux7.1.8 <= 7.1.*unaffected
LinuxLinux7.2 <= *unaffected

Weaknesses

References