CVE-2023-52628: netfilter: nftables: exthdr: fix 4-byte stack OOB write

Severity: high (CVSS 7.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-03-28 · updated 2026-08-04
Weakness: CWE-787

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nftables: exthdr: fix 4-byte stack OOB write If priv->len is a multiple of 4, then dst[len / 4] can write past the destination array which leads to stack corruption. This construct is necessary to clean the remainder of the register in case ->len is NOT a multiple of the register size, so make it conditional just like nft_payload.c does. The bug was added in 4.1 cycle and then copied/inherited when tcp/sctp and ip option support was added. Bug reported by Zero Day Initiative project (ZDI-CAN-21950, ZDI-CAN-21951, ZDI-CAN-21961).

Affected products

Linux kernel: from 4.1 before 5.10.198; from 5.11 before 5.15.132; from 5.16 before 6.1.54; from 6.2 before 6.5.4 — fixed in 5.10.198, 5.15.132, 6.1.54, 6.5.4

How to fix

Upgrade to a fixed version: Linux kernel 5.10.198, 5.15.132, 6.1.54, 6.5.4. Check the vendor advisory for mitigations.

References

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