CVE-2026-74657

CVE CVE-2026-74657EUVD EUVD-2026-64594Published 2026-08-22T15:32:31.000ZLast changed 2026-08-27T12:39:57.000Z

What the advisory describes

In the Linux kernel, the following vulnerability has been resolved: ipv4: Fix fib_nlmsg_size() for RTA_VIA nexthops fib_nlmsg_size() still estimates nexthop space as if every gateway is encoded as an IPv4 RTA_GATEWAY attribute. IPv4 routes can also carry an IPv6 gateway, which fib_nexthop_info() dumps as RTA_VIA. As a result, route notifications can allocate an skb that is too small. fib_dump_info() then fails with -EMSGSIZE and rtmsg_fib() hits the WARN_ON() that marks such failures as a fib_nlmsg_size() bug. With panic_on_warn set, this becomes a kernel panic. Mirror the actual nexthop dump layout in fib_nlmsg_size(): account for IPv6 nexthop gateways dumped as RTA_VIA, for the no-header rtnexthop layout used inside RTA_MULTIPATH, and for RTA_FLOW only when it is actually present.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Linux — Linux patch: 5.10.267; d15662682db232da77136cd348f4c9df312ca6f9 <0f0ca602941d0a81ae9514943ca06c55159c6385; patch: 5.15.216; patch: 6.12.104; d15662682db232da77136cd348f4c9df312ca6f9 <57195f0ab5cfbb5ee0864e5aff15ceb48f5a5e28; d15662682db232da77136cd348f4c9df312ca6f9 <4a5dfbae5179f6574695012a980476254df2d295; patch: 6.1.183; patch: 0; patch: 7.1.9; d15662682db232da77136cd348f4c9df312ca6f9 <4ff9548d84945d2cbf9e4c207288063a200ea397; d15662682db232da77136cd348f4c9df312ca6f9 <7f80ad373ce4a7af5367ff273cea0f16e91387f3; d15662682db232da77136cd348f4c9df312ca6f9 <9b22f13524fa0de0d963bbd3002df6c28bae3395; patch: 7.2; patch: 6.18.45; 5.2; d15662682db232da77136cd348f4c9df312ca6f9 <a59edda6eda1252340354322d8ab318b2e9052fb; d15662682db232da77136cd348f4c9df312ca6f9 <5307a53599fa762c06e475ee4a375252074fd324; patch: 6.6.152

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

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Linux — Linux

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