SB20260905162 - Infinite loop in Linux kernel ipv4



SB20260905162 - Infinite loop in Linux kernel ipv4

Published: September 5, 2026

Security Bulletin ID SB20260905162
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Denial of service

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Infinite loop (CVE-ID: CVE-2026-80793)

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]


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

The vulnerability exists due to improper validation of the effective MTU in ip_do_fragment() when fragmenting IPv4 packets with an effective MTU smaller than the IPv4 header length plus 8 bytes. A remote attacker can send a packet requiring fragmentation over an affected route or device to cause a denial of service.

The issue can occur while forwarding packets to a device with an MTU of 20 bytes.


Remediation

Install update from vendor's website.