CyberSecBulletin
CVE-2026-43502NVD status: Modified

Linux: Missing Release of Memory after Effective Lifetime

Published Updated By the CyberSecBulletin desk

CVE-2026-43502 is a high-severity missing release of memory after effective lifetime 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 e9aefdc5c53fe9aed108c14e3d155710a1bb14c9, 46662f7dc59475995609bf3e9d27eb36f4acf26f, 1e262db7675e27f42c3f3f47d6011855f4454f24 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 0.32% 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 e9aefdc5c53fe9aed108c14e3d155710a1bb14c9 or 46662f7dc59475995609bf3e9d27eb36f4acf26f or 1e262db7675e27f42c3f3f47d6011855f4454f24 or 21d70744e6d3bbf9293aa1ee6fba7c53ad75275e, whichever matches your release line, or a later version.
  2. Update Linux Kernel to 5.10.258 or 5.15.209 or 6.1.175 or 6.6.140, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, e9aefdc5c53fe9aed108c14e3d155710a1bb14c9; 0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, 46662f7dc59475995609bf3e9d27eb36f4acf26f; 0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, 1e262db7675e27f42c3f3f47d6011855f4454f24; 0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, 21d70744e6d3bbf9293aa1ee6fba7c53ad75275e; 0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, 3abc8983b2bae3f487f77d9da5527d7d6b210d46; 0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, 14ef6fd18db2494098b21e0471bf27a1d8e9993e; 0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, 0f5c185fc79a59ee9991234dd6d2a3e5afa6e75b; 0cebaccef3acbdfbc2d85880a2efb765d2f4e2e3 up to, but not including, 44b550d88b267320459d518c0743a241ab2108fa; and 1 more rangese9aefdc5c53fe9aed108c14e3d155710a1bb14c9, 46662f7dc59475995609bf3e9d27eb36f4acf26f, 1e262db7675e27f42c3f3f47d6011855f4454f24, 21d70744e6d3bbf9293aa1ee6fba7c53ad75275e, 3abc8983b2bae3f487f77d9da5527d7d6b210d46, 14ef6fd18db2494098b21e0471bf27a1d8e9993e
SiemensSIMATIC S7-1500 TM MFP - GNU/Linux subsystemall versionsNot stated
LinuxLinux Kernel4.17 up to, but not including, 5.10.258; 5.11 up to, but not including, 5.15.209; 5.16 up to, but not including, 6.1.175; 6.2 up to, but not including, 6.6.140; 6.7 up to, but not including, 6.12.88; 6.13 up to, but not including, 6.18.30; 6.19 up to, but not including, 7.0.7; 7.15.10.258, 5.15.209, 6.1.175, 6.6.140, 6.12.88, 6.18.30

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: net/rds: handle zerocopy send cleanup before the message is queued A zerocopy send can fail after user pages have been pinned but before the message is attached to the sending socket. The purge path currently infers zerocopy state from rm->m_rs, so an unqueued message can be cleaned up as if it owned normal payload pages. However, zerocopy ownership is really determined by the presence of op_mmp_znotifier, regardless of whether the message has reached the socket queue. Capture op_mmp_znotifier up front in rds_message_purge() and use it as the cleanup discriminator. If the message is already associated with a socket, keep the existing completion path. Otherwise, drop the pinned page accounting directly and release the notifier before putting the payload pages. This keeps early send failure cleanup consistent with the zerocopy lifetime rules without changing the normal queued completion path.

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

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Missing Release of Memory after Effective Lifetime vulnerabilities

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