SB2026092826 - Incorrect calculation in Linux kernel netfilter



SB2026092826 - Incorrect calculation in Linux kernel netfilter

Published: September 28, 2026 Updated: September 30, 2026

Security Bulletin ID SB2026092826
CSH Severity
Low
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Information disclosure

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Incorrect calculation (CVE-ID: CVE-2026-100070)

CWE-ID: CWE-682 - Incorrect Calculation

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]


The vulnerability allows a remote attacker to disclose internal network details.

The vulnerability exists due to an incorrect calculation of the Contact-header parsing offset in nf_nat_sip when processing a SIP packet whose NAT address translation changes its length. A remote attacker can send a SIP packet containing subsequent Contact headers to disclose internal network details.

Exploitation requires NAT address translation to shorten the packet.


Remediation

Install update from vendor's website.