9.3 Critical

CVE-2026-99999 In the Linux kernel, the following vulnerability has been resolved: ipv4: validate checksum_start before completing…

Description

In the Linux kernel, the following vulnerability has been resolved: ipv4: validate checksum_start before completing checksum If a packet with bad checksum metadata gets into the ipv4 stack, skb_checksum_help can corrupt the network header and cause a bunch of mischief. This was discovered and reported by Paulos, and has been reporoduced by others independently since. We really shouldn't allow such packets in, but as a defence in depth measure, let's also check before we complete the checksum. A more complete validation at input is forthcoming, but needs more work.

Affected products and versions

Product	Affected versions	Fixed in
Linux 7.3	earliest → < 7.3	7.3
Linux 7.2	earliest → < 7.2.11	7.2.11
Linux 6.18	earliest → < 6.18.57	6.18.57
Linux 6.12	earliest → < 6.12.113	6.12.113
Linux 6.6	earliest → < 6.6.159	6.6.159
Linux 6.1	earliest → < 6.1.190	6.1.190
Linux 5.15	earliest → < 5.15.223	5.15.223
Linux 5.10	earliest → < 5.10.272	5.10.272
Linux	2.6.27	No fix stated