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TI-2026-24342 Aliases CVE-2026-31786GHSA-7p99-gmjx-2f7r

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

Priority LOW 35CWE-120Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 14 fixed, 3 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-120 and the CVSS impact.

Summary

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00197 9th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.10.254, 5.15.204, 6.1.170 +5Red Hat: 4 advisoriesRed Hat: 14 fixed, 3 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux4.13 and later5.10.254, 5.15.204, 6.1.170, 6.6.137, 6.12.85, 6.18.26, 7.0.3, 7.1Patch availableCNA
  • Linux VendorLinux Affected 4.13 and later Fixed in 5.10.254, 5.15.204, 6.1.170, 6.6.137, 6.12.85, 6.18.26, 7.0.3, 7.1 Patch available CNA

CPE configurations NVD · 3

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*4.13 to before 5.10.254; 5.11 to before 5.15.204; 5.16 to before 6.1.170; 6.2 to before 6.6.137; 6.7 to before 6.12.85; 6.13 to before 6.18.26; 6.19 to before 7.0.3VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:*7.1 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:*7.1 rc2VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 4.13 to before 5.10.254; 5.11 to before 5.15.204; 5.16 to before 6.1.170; 6.2 to before 6.6.137; 6.7 to before 6.12.85; 6.13 to before 6.18.26; 6.19 to before 7.0.3 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* Versions 7.1 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* Versions 7.1 rc2 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.10.254, 5.15.204, 6.1.170, 6.6.137, 6.12.85, 6.18.26, 7.0.3, 7.1

Red Hat 4 advisories

  • RHSA-2026:27288 Released 2026-06-20 · Red Hat rating Important
    kernel security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream (v. 10) kernel-64k-debug-devel-6.12.0-211.26.1.el10_2, kernel-64k-debug-devel-matched-6.12.0-211.26.1.el10_2, kernel-64k-devel-6.12.0-211.26.1.el10_2 +12
    • Red Hat Enterprise Linux BaseOS (v. 10) kernel-6.12.0-211.26.1.el10_2, kernel-64k-6.12.0-211.26.1.el10_2, kernel-64k-core-6.12.0-211.26.1.el10_2 +29
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) kernel-tools-libs-devel-6.12.0-211.26.1.el10_2, libperf-6.12.0-211.26.1.el10_2
    • Red Hat Enterprise Linux Real Time (v. 10) kernel-rt-6.12.0-211.26.1.el10_2, kernel-rt-64k-6.12.0-211.26.1.el10_2, kernel-rt-64k-core-6.12.0-211.26.1.el10_2 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 10) kernel-rt-6.12.0-211.26.1.el10_2, kernel-rt-core-6.12.0-211.26.1.el10_2, kernel-rt-debug-6.12.0-211.26.1.el10_2 +9
  • RHSA-2026:26427 Released 2026-06-16 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux BaseOS (v. 8) bpftool-4.18.0-553.134.1.el8_10, kernel-4.18.0-553.134.1.el8_10, kernel-abi-stablelists-4.18.0-553.134.1.el8_10 +19
    • Red Hat Enterprise Linux CRB (v. 8) kernel-tools-libs-devel-4.18.0-553.134.1.el8_10
  • RHSA-2026:26428 Released 2026-06-16 · Red Hat rating Important
    kernel-rt security update
    • Red Hat Enterprise Linux NFV (v. 8) kernel-rt-4.18.0-553.134.1.rt7.475.el8_10, kernel-rt-core-4.18.0-553.134.1.rt7.475.el8_10, kernel-rt-debug-4.18.0-553.134.1.rt7.475.el8_10 +9
    • Red Hat Enterprise Linux RT (v. 8) kernel-rt-4.18.0-553.134.1.rt7.475.el8_10, kernel-rt-core-4.18.0-553.134.1.rt7.475.el8_10, kernel-rt-debug-4.18.0-553.134.1.rt7.475.el8_10 +7
Show 1 more Red Hat advisories
  • RHSA-2026:24381 Released 2026-06-08 · Red Hat rating Important
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-687.13.1.el9_8, kernel-64k-debug-devel-matched-5.14.0-687.13.1.el9_8, kernel-64k-devel-5.14.0-687.13.1.el9_8 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-687.13.1.el9_8, kernel-64k-5.14.0-687.13.1.el9_8, kernel-64k-core-5.14.0-687.13.1.el9_8 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-687.13.1.el9_8, libperf-5.14.0-687.13.1.el9_8
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-687.13.1.el9_8, kernel-rt-64k-5.14.0-687.13.1.el9_8, kernel-rt-64k-core-5.14.0-687.13.1.el9_8 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-687.13.1.el9_8, kernel-rt-core-5.14.0-687.13.1.el9_8, kernel-rt-debug-5.14.0-687.13.1.el9_8 +9

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:24381
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:26427
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:24381
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:26427
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:24381
Red Hat Enterprise Linux NFV (v. 8)Fixed RHSA-2026:26428
Red Hat Enterprise Linux RT (v. 8)Fixed RHSA-2026:26428
Red Hat Enterprise Linux Real Time (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2026:24381
Red Hat Enterprise Linux Real Time for NFV (v. 10)Fixed RHSA-2026:27288
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2026:24381

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-31786
  2. 2026-10-03 Alias added: GHSA-7p99-gmjx-2f7r
  3. 2026-10-16 CISA SSVC decision points changed
  4. 2026-10-19 Weakness changed · CISA ADP

References

Patch 8

Advisory 2

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences