High 7.8Published Dec 4, 2025

CVE-2025-40248vsock: Ignore signal/timeout on connect() if already established

Updated under an hour ago (Oct 26, 2026, 1:30 PM ET)

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Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: vsock: Ignore signal/timeout on connect() if already established During connect(), acting on a signal/timeout by disconnecting an already established socket leads to several issues: 1. connect() invoking vsock_transport_cancel_pkt() -> virtio_transport_purge_skbs() may race with sendmsg() invoking virtio_transport_get_credit(). This results in a permanently elevated `vvs->bytes_unsent`. Which, in turn, confuses the SOCK_LINGER handling. 2. connect() resetting a connected socket's state may race with socket being placed in a sockmap. A disconnected socket remaining in a sockmap breaks sockmap's assumptions. And gives rise to WARNs. 3. connect() transitioning SS_CONNECTED -> SS_UNCONNECTED allows for a transport change/drop after TCP_ESTABLISHED. Which poses a problem for any simultaneous sendmsg() or connect() and may result in a use-after-free/null-ptr-deref. Do not disconnect socket on signal/timeout. Keep the logic for unconnected sockets: they don't linger, can't be placed in a sockmap, are rejected by sendmsg(). [1]: https://lore.kernel.org/netdev/e07fd95c-9a38-4eea-9638-133e38c2ec9b@rbox.co/ [2]: https://lore.kernel.org/netdev/20250317-vsock-trans-signal-race-v4-0-fc8837f3f1d4@rbox.co/ [3]: https://lore.kernel.org/netdev/60f1b7db-3099-4f6a-875e-af9f6ef194f6@rbox.co/

CVSS: 7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): Not given
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Deferred
Record last updated: Aug 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	from d021c344051af91f42c5ba9fdedc176740cbd238 before 3f71753935d648082a8279a97d30efe6b85be680; from d021c344051af91f42c5ba9fdedc176740cbd238 before da664101fb4a0de5cb70d2bae6a650df954df2af; from d021c344051af91f42c5ba9fdedc176740cbd238 before 67432915145848658149683101104e32f9fd6559; from d021c344051af91f42c5ba9fdedc176740cbd238 before eeca93f06df89be5a36305b7b9dae1ed65550dfc; from d021c344051af91f42c5ba9fdedc176740cbd238 before 5998da5a8208ae9ad7838ba322bccb2bdcd95e81; from d021c344051af91f42c5ba9fdedc176740cbd238 before f1c170cae285e4b8f61be043bb17addc3d0a14b5; from d021c344051af91f42c5ba9fdedc176740cbd238 before ab6b19f690d89ae4709fba73a3c4a7911f495b7a; from d021c344051af91f42c5ba9fdedc176740cbd238 before 002541ef650b742a198e4be363881439bb9d86b4	CNA record
Siemens RUGGEDCOM RST2428P siemens:ruggedcom_rst2428p (from the name)	before V4.0	CISA ADP

References

References

https://git.kernel.org/stable/c/3f71753935d648082a8279a97d30efe6b85be680
https://git.kernel.org/stable/c/da664101fb4a0de5cb70d2bae6a650df954df2af
https://git.kernel.org/stable/c/67432915145848658149683101104e32f9fd6559
https://git.kernel.org/stable/c/eeca93f06df89be5a36305b7b9dae1ed65550dfc
https://git.kernel.org/stable/c/5998da5a8208ae9ad7838ba322bccb2bdcd95e81
https://git.kernel.org/stable/c/f1c170cae285e4b8f61be043bb17addc3d0a14b5
https://git.kernel.org/stable/c/ab6b19f690d89ae4709fba73a3c4a7911f495b7a
https://git.kernel.org/stable/c/002541ef650b742a198e4be363881439bb9d86b4
https://cert-portal.siemens.com/productcert/html/ssa-253495.html

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.