SB2026062655 - Stack-based buffer overflow in Linux kernel netfilter
Published: June 26, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Stack-based buffer overflow (CVE-ID: CVE-2026-53267)
CWE-ID: CWE-121 - Stack-based buffer overflow
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to cause memory corruption.
The vulnerability exists due to a stack-based buffer overflow in nft_ct_get_eval and nft_ct_get_fast_eval in the netfilter nft_ct subsystem when processing a crafted nftables rule that uses a template conntrack object. A local user can create a crafted rule sequence to cause memory corruption.
The issue is triggered when a conntrack template created by a preceding expression is treated as a real conntrack entry by a subsequent expression on the same skb.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/2e154b5f53f1b0b490c7b8b02499f90feb86b1d5
- https://git.kernel.org/stable/c/3027ecbdb5fdf9200251c21d4818e4c447ef78e1
- https://git.kernel.org/stable/c/8470f676eadeab99132708acb1a85915664d6115
- https://git.kernel.org/stable/c/af80f78ce984649e1698b841cd33f4fa505ad828
- https://git.kernel.org/stable/c/f071b0bf078146368d18e4eec386bf2ddc0ab7e0