NULL pointer dereference in Linux kernel - CVE-2026-99155
Published: October 29, 2026
Vulnerability identifier: #VU158436
CSH Severity: Low
CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-99155
CWE-ID: CWE-476
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local privileged user to cause a denial of service by crashing a guest operating system.
The vulnerability exists due to a NULL pointer dereference in the Linux kernel Xen SCSI frontend function scsifront_do_response() when processing a backend response with an in-range request identifier that selects an unpopulated shadow slot. A local privileged user can control a malicious backend and return a spurious response or a duplicate response for a completed request to crash the guest.
Affected software
Linux kernel
Debian Linux
linux (Debian package)
Debian Linux
linux (Debian package)
How to mitigate CVE-2026-99155
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3
linux (Debian package) - update to 6.12.115-2
linux (Debian package) - update to 6.12.115-2