Answer in brief
CVE-2026-74581 records a Critical severity (CVSS 9.8) vulnerability in net: ipv6: clear suppressed fib6 rule result. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 9.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=209d35ee34e25f9668c404350a1c86d914c54ffa <90c57310e266eb94e4a80d6b15a9ca131d2e82cb || >=8ef8a76a340ebdb2c2eea3f6fb0ebbed09a16383 <5d29b286c9de0b309e94b9ed083aa1a2f429434f || >=cdef485217d30382f3bf6448c54b4401648fe3f1 <354db6243eca59e9d187ffbf8b7955b044ce84dc || >=cdef485217d30382f3bf6448c54b4401648fe3f1 <6d98c70fe0ba8c7708bfd5b2a5174d2086775daa || >=cdef485217d30382f3bf6448c54b4401648fe3f1 <9bad152c42b37499162367fe47867411e62fffa3 || >=cdef485217d30382f3bf6448c54b4401648fe3f1 <dc3ab04220667f254f4348572b2a0b3febff89fb || >=cdef485217d30382f3bf6448c54b4401648fe3f1 <a341c091ca0bfae377747b1b59a3bd8ebe18a937 || >=cdef485217d30382f3bf6448c54b4401648fe3f1 <6aea62e433fe1b586202a5fee8b5807ce635e1d7 || ee38eb8cf9a7323884c2b8e0adbbeb2192d31e29 || >=5.10.84 <5.10.265 || >=5.15.7 <5.15.216 || >=5.4.164 <5.5 | 90c57310e266eb94e4a80d6b15a9ca131d2e82cb, 5d29b286c9de0b309e94b9ed083aa1a2f429434f, 354db6243eca59e9d187ffbf8b7955b044ce84dc, 6d98c70fe0ba8c7708bfd5b2a5174d2086775daa, 9bad152c42b37499162367fe47867411e62fffa3, dc3ab04220667f254f4348572b2a0b3febff89fb, a341c091ca0bfae377747b1b59a3bd8ebe18a937, 6aea62e433fe1b586202a5fee8b5807ce635e1d7, 5.10.265, 5.15.216, 5.5 |
| Linux/Linuxgeneric | 5.16 | Not reported |
Published upstream
Aug 21, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 25, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 21, 2026
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.
Quoted source text, attributed separately from HOL analysis.