Description
In the Linux kernel before 5.3.4, fib6_rule_lookup in net/ipv6/ip6_fib.c mishandles the RT6_LOOKUP_F_DST_NOREF flag in a reference-count decision, leading to (for example) a crash that was identified by syzkaller, aka CID-7b09c2d052db.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 24.04 LTS | linux-raspi-realtime | No fix yet | — |
| Ubuntu 22.04 LTS | linux-riscv +2 | No fix yet | — |
| Ubuntu 20.04 LTS | linux-gke +3 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-gcp-edge +1 | No fix yet | — |
| Ubuntu 18.04 LTS | linux-hwe-edge | 5.3.0-22.24~18.04.1 | — |
| Ubuntu 16.04 LTS | linux-hwe-edge | No fix yet | — |