Memory leak in Linux kernel - CVE-2026-74625

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper resource management in nf_ct_bridge_pre() when processing non-IPv4 and non-IPv6 Ethernet frames after a bridge nftables ct zone set rule has attached a conntrack template. A remote attacker can send specially crafted non-IP traffic to cause a denial of service.

Memory is leaked by making the existing conntrack template reference unreachable, which can exhaust slab memory.

Affected software

How to mitigate CVE-2026-74625

External References

• https://git.kernel.org/stable/c/46d559f00b1ab1d114f92d2f16c5ef0093b3b9dd
• https://git.kernel.org/stable/c/6ea88401e10e04e0b3bb7a7adea54932fb60b93b
• https://git.kernel.org/stable/c/7cff440d702616022769f2643168d7f9820547a0
• https://git.kernel.org/stable/c/bd7b16494dacf87e9336a1dcfdada83b9e40edd6
• https://git.kernel.org/stable/c/c58d34fe8b7e47bb0b350a7625023b1261342be5
• https://git.kernel.org/stable/c/d45cc8020d7c0a9f01dee42ff5c40bc14c9af72f
• https://git.kernel.org/stable/c/daa6e070f8e1e7a4dddec8b64ca37663f8cda917
• https://git.kernel.org/stable/c/fc90df37540627d092af770215fb4b7befe9409b

Related Security Bulletins

• Memory leak in Linux kernel bridge netfilter
• Debian update for linux