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CVE PROGRAM SOURCE RECORD7.8 High

CVE-2026-31786

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

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Status
Published
Published
Updated
Assigning organization
Linux

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

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < e3af585e1728c917682b6a3de9a69b41fb9194d4affected
  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < 8288d031a01dbacfde3fc643f7be3d23504de64daffected
  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < f458ba102da97fafca106327086fc95f3fc764cbaffected
  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < 4b4defd2fce3f966c25adabf46644a85558f1169affected
  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < 5c5ff7c7bd15bb536f44b10b3fb5b8408f344d0aaffected
  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < d5f59216650c51e5e3fcb7517c825bc8047f60efaffected
  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < 52cecff98bda2c51eed1c6ce9d21c5d6268fb19daffected
  • 84b7625728ea311ea35bdaa0eded53c1c56baeaa to < 27fdbab4221b375de54bf91919798d88520c6e28affected

Linux Linux

Default version status: affected

  • 4.13affected
  • 0 to < 4.13unaffected
  • 5.10.254 to ≤ 5.10.*unaffected
  • 5.15.204 to ≤ 5.15.*unaffected
  • 6.1.170 to ≤ 6.1.*unaffected
  • 6.6.137 to ≤ 6.6.*unaffected
  • 6.12.85 to ≤ 6.12.*unaffected
  • 6.18.26 to ≤ 6.18.*unaffected
  • 7.0.3 to ≤ 7.0.*unaffected
  • 7.1 to ≤ *unaffected

References