Linux: Missing Release of Memory after Effective Lifetime
CVE-2026-46309 is a high-severity missing release of memory after effective lifetime vulnerability in Linux, with a CVSS 3.1 base score of 7.0 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 87f9b1528e1ffc1da3615d552c9a06aba5e20b00, fea04cf6f2345bc50f15b6638906c35962b89424, 4e5591c2fc1b30f4ea5e2eab4c3a695acc404e39 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 0.13% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Linux to 87f9b1528e1ffc1da3615d552c9a06aba5e20b00 or fea04cf6f2345bc50f15b6638906c35962b89424 or 4e5591c2fc1b30f4ea5e2eab4c3a695acc404e39, whichever matches your release line, or a later version.
- Update Linux Kernel to 6.18.32 or 7.0.9, whichever matches your release line, or a later version.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Linux | Linux | ada7486c5668db542a7d361268df931aca5b726a up to, but not including, 87f9b1528e1ffc1da3615d552c9a06aba5e20b00; ada7486c5668db542a7d361268df931aca5b726a up to, but not including, fea04cf6f2345bc50f15b6638906c35962b89424; ada7486c5668db542a7d361268df931aca5b726a up to, but not including, 4e5591c2fc1b30f4ea5e2eab4c3a695acc404e39; 6.18 | 87f9b1528e1ffc1da3615d552c9a06aba5e20b00, fea04cf6f2345bc50f15b6638906c35962b89424, 4e5591c2fc1b30f4ea5e2eab4c3a695acc404e39 |
| Red Hat | Red Hat Enterprise Linux 10 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 6 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 7 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 8 | Not specified in the record | Not stated |
| Red Hat | Red Hat Enterprise Linux 9 | Not specified in the record | Not stated |
| Linux | Linux Kernel | 6.18 up to, but not including, 6.18.32; 6.19 up to, but not including, 7.0.9; 7.1 | 6.18.32, 7.0.9 |
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
- HighSuccess depends on conditions outside the attacker's control.
- 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:H/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 7.0 | High | NVD |
| CVSS 3.1 | 7.0 | High | CNA |
Official description
In the Linux kernel, the following vulnerability has been resolved: drm/xe/uapi: Reject coh_none PAT index for CPU cached memory in madvise Add validation in xe_vm_madvise_ioctl() to reject PAT indices with XE_COH_NONE coherency mode when applied to CPU cached memory. Using coh_none with CPU cached buffers is a security issue. When the kernel clears pages before reallocation, the clear operation stays in CPU cache (dirty). GPU with coh_none can bypass CPU caches and read stale sensitive data directly from DRAM, potentially leaking data from previously freed pages of other processes. This aligns with the existing validation in vm_bind path (xe_vm_bind_ioctl_validate_bo). v2(Matthew brost) - Add fixes - Move one debug print to better place v3(Matthew Auld) - Should be drm/xe/uapi - More Cc v4(Shuicheng Lin) - Fix kmem leak issues by the way v5 - Remove kmem leak because it has been merged by another patch v6 - Remove the fix which is not related to current fix v7 - No change v8 - Rebase v9 - Limit the restrictions to iGPU v10 - No change (cherry picked from commit 016ccdb674b8c899940b3944952c96a6a490d10a)
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Missing Release of Memory after Effective Lifetime
The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.
How developers prevent this class of flaw
- Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone. For example, glibc in Linux provides protection against free of invalid pointers. When using Xcode to target OS X or iOS, enable automatic reference counting (ARC). To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std
- Use an abstraction library to abstract away risky APIs. Not a complete solution.
- Consider using the Boehm-Demers-Weiser garbage collector (bdwgc), which can help avoid leaks.
More Missing Release of Memory after Effective Lifetime vulnerabilities (CWE-401)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Patches and release notes
Third-party and government advisories
- access.redhat.com/security/cve/CVE-2026-46309Third Party Advisory
- bugzilla.redhat.com/show_bug.cgi?id=2486468Third Party Advisory
- security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46309.jsonThird Party Advisory
Recent Missing Release of Memory after Effective Lifetime vulnerabilities
- 8.2 High severity
- 9.8 Critical severity
- 7.8 High severity
- 7.8 High severity
- 7.5 High severity
- 7.5 High severity
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