#VU124173 NULL Pointer Dereference in Linux kernel - CVE-2026-23277
Published: March 20, 2026
Vulnerability identifier: #VU124173
Vulnerability risk: Medium
CVSSv4.0: 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/E:U/U:Green
CVE-ID: CVE-2026-23277
CWE-ID: CWE-476
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
Linux kernel
Linux kernel
Software vendor:
Linux Foundation
Linux Foundation
Description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to a NULL pointer dereference in the teql network scheduler component when handling packet transmission through a gretap tunnel configured as a TEQL slave. A remote attacker can send a specially crafted network request to trigger a NULL pointer dereference in iptunnel_xmit, leading to a kernel page fault and system crash.
Exploitation does not require authentication or elevated privileges. The issue arises because the skb->dev field is not updated to the slave device before transmission, causing iptunnel_xmit_stats to access uninitialized tstats via a NULL pointer.
Remediation
Install security update from vendor's repository.