SB20260917179 - Division by zero in Linux kernel ipv6
Published: September 17, 2026
Security Bulletin ID
SB20260917179
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Division by zero (CVE-ID: CVE-2026-89790)
CWE-ID: CWE-369 - Divide By Zero
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a divide-by-zero error in rt6_multipath_rebalance() when a concurrent ignore_routes_with_linkdown update causes the total eligible nexthop weight to be zero. A local user can concurrently update ignore_routes_with_linkdown while adding an IPv6 multipath route to cause a denial of service.
Remediation
Install update from vendor's website.