CyberSecBulletin
CVE-2026-68264NVD status: Received

Linux: Out-of-bounds Write

Published Updated By the CyberSecBulletin desk

CVE-2026-68264 is a high-severity out-of-bounds write vulnerability in Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions be5c39730ab8f1dfe59983bf7d8e3705541d1fee, 157b1e3384d7d37f59c0c2b2ff2af8f557db1daa, 90e4fd331b980259c40118d05b89b0ec514e7c48 as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.14% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to be5c39730ab8f1dfe59983bf7d8e3705541d1fee or 157b1e3384d7d37f59c0c2b2ff2af8f557db1daa or 90e4fd331b980259c40118d05b89b0ec514e7c48 or 6384271ac1ac0099198d15df79212a19ebdb929d, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxe8babb280b5ef904df54b3a90e5a7e3a9600c4a9 up to, but not including, be5c39730ab8f1dfe59983bf7d8e3705541d1fee; e8babb280b5ef904df54b3a90e5a7e3a9600c4a9 up to, but not including, 157b1e3384d7d37f59c0c2b2ff2af8f557db1daa; e8babb280b5ef904df54b3a90e5a7e3a9600c4a9 up to, but not including, 90e4fd331b980259c40118d05b89b0ec514e7c48; e8babb280b5ef904df54b3a90e5a7e3a9600c4a9 up to, but not including, 6384271ac1ac0099198d15df79212a19ebdb929d; 6.12be5c39730ab8f1dfe59983bf7d8e3705541d1fee, 157b1e3384d7d37f59c0c2b2ff2af8f557db1daa, 90e4fd331b980259c40118d05b89b0ec514e7c48, 6384271ac1ac0099198d15df79212a19ebdb929d

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: drm/xe/pt: Reset current_op in xe_pt_update_ops_init() xe_pt_update_ops_init() fails to reset current_op to 0. On the vm_bind path, ops_execute() calls xe_pt_update_ops_prepare() inside the xe_validation_guard() / drm_exec_until_all_locked() loop. When that loop retries due to lock contention or OOM eviction (drm_exec_retry_on_contention() / xe_validation_retry_on_oom()), xe_pt_update_ops_prepare() runs again on the same vops, and each call to bind_op_prepare() increments current_op without resetting it. After N retries current_op exceeds the array size allocated by xe_vma_ops_alloc(), causing an out-of-bounds write into SLUB-poisoned memory and a subsequent UAF crash in xe_migrate_update_pgtables_cpu() when reading the corrupted pt_op->bind. Also reset needs_svm_lock and needs_invalidation which are derived in the same prepare pass and would otherwise cause wrong migrate ops selection and redundant TLB invalidation on retry. Fix this by resetting current_op, needs_svm_lock and needs_invalidation in xe_pt_update_ops_init(). v2 (Matt): - Add details in commit message. - Add Fixes tag and Cc to [email protected] (cherry picked from commit 046045543e530605c441063535e7dca0075369a6)

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Write

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

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Write vulnerabilities

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