CVE-2026-43216
What it is
In the Linux kernel, the following vulnerability has been resolved: net: Drop the lock in skb_may_tx_timestamp() skb_may_tx_timestamp() may acquire sock::sk_callback_lock. The lock must not be taken in IRQ context, only softirq is okay. A few drivers receive the timestamp via a dedicated interrupt and complete the TX timestamp from that handler. This will lead to a deadlock if the lock is already write-locked on the same CPU. Taking the lock can be avoided. The socket (pointed by the skb) will remain valid until the skb is released. The ->sk_socket and ->file member will be set to NULL once the user closes the socket which may happen before the timestamp arrives. If we happen to observe the pointer while the socket is closing but before the pointer is set to NULL then we may use it because both pointer (and the file's cred member) are RCU freed. Drop the lock. Use READ_ONCE() to obtain the individual pointer. Add a matching WRITE_ONCE() where the pointer are cleared.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-476 · NULL pointer dereference
- Record status
- Modified
Affected
- Linux Kernel < 6.18.16
- Linux Kernel < 6.19.6
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-43216.md and follow it. Check whether this project is affected by CVE-2026-43216. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/983512f3a87fd8dc4c94dfa6b596b6e57df5aad7
- https://git.kernel.org/stable/c/e4c6efb3b70ff87f1df99efce2f8893717695718
- https://git.kernel.org/stable/c/f3e4cceafad27c9363c33622732f86722846ec6f
References
- https://git.kernel.org/stable/c/3709d73ace37e9aaebb688f5a5cf706d74350b64
- https://git.kernel.org/stable/c/4839cbda8f13e99ce2bb3b593f5cc3288415684b
- https://git.kernel.org/stable/c/983512f3a87fd8dc4c94dfa6b596b6e57df5aad7
- https://git.kernel.org/stable/c/c770217044d9cbe16a1f7c385cf080ed06a2fc04
- https://git.kernel.org/stable/c/cd2463ec60f0d6e460078037c86f9d0947ee1ff6
- https://git.kernel.org/stable/c/cf7599116c4c0082fd25cb1bf0254631da0ed06e
- https://git.kernel.org/stable/c/e4c6efb3b70ff87f1df99efce2f8893717695718
- https://git.kernel.org/stable/c/f3e4cceafad27c9363c33622732f86722846ec6f
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-457936.html