Description
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
Product status
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before e3af585e1728c917682b6a3de9a69b41fb9194d4
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before 8288d031a01dbacfde3fc643f7be3d23504de64d
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before f458ba102da97fafca106327086fc95f3fc764cb
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before 4b4defd2fce3f966c25adabf46644a85558f1169
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before 5c5ff7c7bd15bb536f44b10b3fb5b8408f344d0a
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before d5f59216650c51e5e3fcb7517c825bc8047f60ef
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before 52cecff98bda2c51eed1c6ce9d21c5d6268fb19d
84b7625728ea311ea35bdaa0eded53c1c56baeaa (git) before 27fdbab4221b375de54bf91919798d88520c6e28
4.13
Any version before 4.13
5.10.254 (semver)
5.15.204 (semver)
6.1.170 (semver)
6.6.137 (semver)
6.12.85 (semver)
6.18.26 (semver)
7.0.3 (semver)
7.1-rc2 (original_commit_for_fix)
References
www.openwall.com/lists/oss-security/2026/04/28/12
xenbits.xen.org/xsa/advisory-485.html
git.kernel.org/...c/e3af585e1728c917682b6a3de9a69b41fb9194d4
git.kernel.org/...c/8288d031a01dbacfde3fc643f7be3d23504de64d
git.kernel.org/...c/f458ba102da97fafca106327086fc95f3fc764cb
git.kernel.org/...c/4b4defd2fce3f966c25adabf46644a85558f1169
git.kernel.org/...c/5c5ff7c7bd15bb536f44b10b3fb5b8408f344d0a
git.kernel.org/...c/d5f59216650c51e5e3fcb7517c825bc8047f60ef
git.kernel.org/...c/52cecff98bda2c51eed1c6ce9d21c5d6268fb19d
git.kernel.org/...c/27fdbab4221b375de54bf91919798d88520c6e28