Linux Linux Kernel
CVE-2026-43502
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.
What this means for your business
- It affects Linux Kernel. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it only with access to the machine itself, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.1% chance of attack attempts being seen in the next 30 days, ranking above 2% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Linux Kernel, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
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Scoring
- CVSS
- 7.8 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H- Weakness
- CWE-401
- Assigned by
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Dates
- Published
- 2026-05-21
- Last modified
- 2026-09-15
- Sources
- NVD
Affected products
- Linux Linux Kernel4.17 - 5.10.258, 5.11 - 5.15.209, 5.16 - 6.1.175, 6.2 - 6.6.140, 6.7 - 6.12.88, 6.13 - 6.18.30, 6.19 - 7.0.7, 7.1
As listed in the NVD configuration data. Not a statement about your estate.
References
- https://git.kernel.org/stable/c/0f5c185fc79a59ee9991234dd6d2a3e5afa6e75b
- https://git.kernel.org/stable/c/14ef6fd18db2494098b21e0471bf27a1d8e9993e
- https://git.kernel.org/stable/c/1e262db7675e27f42c3f3f47d6011855f4454f24
- https://git.kernel.org/stable/c/21d70744e6d3bbf9293aa1ee6fba7c53ad75275e
- https://git.kernel.org/stable/c/3abc8983b2bae3f487f77d9da5527d7d6b210d46
- https://git.kernel.org/stable/c/44b550d88b267320459d518c0743a241ab2108fa
- https://git.kernel.org/stable/c/46662f7dc59475995609bf3e9d27eb36f4acf26f
- https://git.kernel.org/stable/c/e9aefdc5c53fe9aed108c14e3d155710a1bb14c9
- https://github.com/NebuSec/CyberMeowfia/tree/main/security-research/Linux-CVE-2026-43502-openSUSE-6.4.0-150600