7.8

CVE-2026-31786

Buffer overflow in drivers/xen/sys-hypervisor.c

In the Linux kernel, the following vulnerability has been resolved:

Buffer overflow in drivers/xen/sys-hypervisor.c

The build id returned by HYPERVISOR_xen_version(XENVER_build_id) is
neither NUL terminated nor a string.

The first causes a buffer overflow as sprintf in buildid_show will
read and copy till it finds a NUL.

00000000  f4 91 51 f4 dd 38 9e 9d  65 47 52 eb 10 71 db 50  |..Q..8..eGR..q.P|
00000010  b9 a8 01 42 6f 2e 32                              |...Bo.2|
00000017

So use a memcpy instead of sprintf to have the correct value:

00000000  f4 91 51 f4 dd 00 9e 9d  65 47 52 eb 10 71 db 50  |..Q.....eGR..q.P|
00000010  b9 a8 01 42                                       |...B|
00000014

(the above have a hack to embed a zero inside and check it's
returned correctly).

This is XSA-485 / CVE-2026-31786
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
LinuxLinux Kernel Version >= 4.13 < 5.10.254
LinuxLinux Kernel Version >= 5.11 < 5.15.204
LinuxLinux Kernel Version >= 5.16 < 6.1.170
LinuxLinux Kernel Version >= 6.2 < 6.6.137
LinuxLinux Kernel Version >= 6.7 < 6.12.85
LinuxLinux Kernel Version >= 6.13 < 6.18.26
LinuxLinux Kernel Version >= 6.19 < 7.0.3
LinuxLinux Kernel Version7.1 Updaterc1
LinuxLinux Kernel Version7.1 Updaterc2
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.2% 0.095
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
416baaa9-dc9f-4396-8d5f-8c081fb06d67 7.8 1.8 5.9
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE-787 Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

https://git.kernel.org/stable/c/4b4defd2fce3f966c25adabf46644a85558f1169
Patch
https://git.kernel.org/stable/c/52cecff98bda2c51eed1c6ce9d21c5d6268fb19d
Patch
https://git.kernel.org/stable/c/5c5ff7c7bd15bb536f44b10b3fb5b8408f344d0a
Patch
https://git.kernel.org/stable/c/8288d031a01dbacfde3fc643f7be3d23504de64d
Patch
https://git.kernel.org/stable/c/d5f59216650c51e5e3fcb7517c825bc8047f60ef
Patch
https://git.kernel.org/stable/c/e3af585e1728c917682b6a3de9a69b41fb9194d4
Patch
https://git.kernel.org/stable/c/f458ba102da97fafca106327086fc95f3fc764cb
Patch
http://www.openwall.com/lists/oss-security/2026/04/28/12
Third Party Advisory
Mailing List
http://xenbits.xen.org/xsa/advisory-485.html
Third Party Advisory
Mailing List
https://git.kernel.org/stable/c/27fdbab4221b375de54bf91919798d88520c6e28
Patch