CVE-2026-74743

CVE CVE-2026-74743EUVD EUVD-2026-66573Published 2026-08-26T14:36:54.000ZLast changed 2026-08-27T05:01:04.000ZCVSS 9.8

What the advisory describes

In the Linux kernel, the following vulnerability has been resolved: macvlan: inherit needed_headroom and needed_tailroom from lowerdev macvlan devices inherit hard_header_len from lowerdev during macvlan_init(), but leave needed_headroom and needed_tailroom set to 0. When the underlying lowerdev requires extra headroom or tailroom for headers/trailers (e.g. macsec, ipsec, wireguard, tunnels, or veth with rx headroom), upper layers calculating packet headroom and tailroom fail to reserve sufficient space. This can result in reallocation overhead, skb headroom underflows, or KASAN slab-use-after-free crashes when dev_hard_header() / macvlan_hard_header() prepends header data or when lower devices append tailroom. Fix this by: 1. Inheriting needed_headroom and needed_tailroom from lowerdev in macvlan_init(). 2. Propagating needed_headroom and needed_tailroom updates to attached macvlans in macvlan_device_event() when receiving NETDEV_FEAT_CHANGE events.

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: 0; b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53 <8f6a05dbac05725e0786701eb04778c5bdbe4eaa; patch: 7.2; b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53 <96fa90b74385b7f2b0d97251dd43d5ee6ca44668; patch: 7.1.10; patch: 6.1.184; b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53 <bc9a00fb78e32bccc39d763bfd13a450705bac5d; patch: 6.12.105; b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53 <cef51860becd9700217c81732ca1eb1ea6ed6fe1; patch: 6.6.153; b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53 <8cd90e850e434577bf6774778657d26d6995e53f; b863ceb7ddcea8c55fcf1d7b2ac591d50aa7ed53 <28afc87bd8da0b3348bbbd834c8a89e83712cf5e; patch: 6.18.46; 2.6.23

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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