CVE-2026-53211 netfilter: nft_meta_bridge: fix stale stack leak via IIFHWADDR register

What is CVE-2026-53211?

CVE-2026-53211 is a medium-severity vulnerability in Linux kernel, published on 25 Jun 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

In the Linux kernel, the following vulnerability has been resolved:

netfilter: nft_meta_bridge: fix stale stack leak via IIFHWADDR register

NFT_META_BRI_IIFHWADDR declares its destination register with len = ETH_ALEN (6 bytes), which the register-init tracking rounds up to two 32-bit registers (8 bytes). nft_meta_bridge_get_eval() then does memcpy(dest, br_dev->dev_addr, ETH_ALEN), writing only 6 bytes and leaving the upper 2 bytes of the second register as uninitialised nft_do_chain() stack. A downstream load of that register span leaks those stale bytes to userspace.

Zero the second register before the memcpy so the full declared span is written.

Weakness: CWE-401

Which versions are affected by CVE-2026-53211?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2026-53211?

Apply the vendor's patch.

Is CVE-2026-53211 being exploited?

There is no known exploitation of CVE-2026-53211 in the wild and no public exploit code.

Other vulnerabilities in Linux kernel

• CVE-2026-53266 Linux Kernel Out-of-Bounds Write Exploited High 8.8
• CVE-2013-6282 Linux Kernel Improper Input Validation Exploited High 8.8
• CVE-2022-0185 Linux Kernel Heap-Based Buffer Overflow Exploited High 8.4
• CVE-2013-2094 Linux Kernel Privilege Escalation Exploited High 8.4
• CVE-2026-53362 Linux Kernel Unspecified Exploited High 7.8

All Linux kernel vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BELL-CVE-2026-53211, DEBIAN-CVE-2026-53211, GHSA-vccq-h5j4-92qr, UBUNTU-CVE-2026-53211.