PT-2026-35873 · Linux · Linux Kernel

Frediano Ziglio · Published 2026-04-28 · Updated 2026-05-06 · CVE-2026-31786

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A buffer overflow exists in the drivers/xen/sys-hypervisor.c file. The build ID returned by the HYPERVISOR xen version(XENVER build id) function is not a string and lacks NUL termination. Consequently, the sprintf() function in buildid show() continues reading and copying data until a NUL character is encountered, leading to a buffer overflow.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Memory Corruption

Weakness Enumeration

CWE-787

Related Identifiers

CVE-2026-31786

ECHO-6451-5EFA-2FD1

OPENSUSE-SU-2026:10703-1

Affected Products

Linux Kernel

References · 88

• https://git.kernel.org/stable/c/d5f59216650c51e5e3fcb7517c825bc8047f60ef · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31786 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31786 · Vendor Advisory
• https://git.kernel.org/stable/c/e3af585e1728c917682b6a3de9a69b41fb9194d4 · Patch
• https://osv.dev/vulnerability/ALPINE-CVE-2026-31786 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:10703-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-31786 · Vendor Advisory
• https://osv.dev/vulnerability/BELL-CVE-2026-31786 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-31786 · Vendor Advisory
• https://git.kernel.org/stable/c/f458ba102da97fafca106327086fc95f3fc764cb · Patch
• https://git.kernel.org/stable/c/4b4defd2fce3f966c25adabf46644a85558f1169 · Patch
• https://git.kernel.org/stable/c/52cecff98bda2c51eed1c6ce9d21c5d6268fb19d · Patch
• https://git.kernel.org/stable/c/27fdbab4221b375de54bf91919798d88520c6e28 · Patch
• https://git.kernel.org/stable/c/8288d031a01dbacfde3fc643f7be3d23504de64d · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-31786 · Security Note