SB2026040693 - NULL pointer dereference in Linux kernel ipv6
Published: April 6, 2026
Security Bulletin ID
SB2026040693
Severity
Medium
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 security vulnerability.
1) NULL pointer dereference (CVE-ID: CVE-2026-23442)
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to a NULL pointer dereference in seg6_hmac_validate_skb() and ipv6_srh_rcv() when processing SRv6 paths on a device without IPv6 configuration. A remote attacker can send specially crafted IPv6 traffic to cause a denial of service.
The issue occurs when __in6_dev_get() returns NULL, such as on a device with no IPv6 configuration, including after device unregister or when the MTU is below the IPv6 minimum MTU.
Remediation
Install update from vendor's website.