CVEvulnerability
CVE-2025-40248
7.8 HIGH
Official page ↗
- Status
- Deferred
- Published
- 2025-12-04
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
- 7.8 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Description
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/[email protected]/
[2]: https://lore.kernel.org/netdev/[email protected]/
[3]: https://lore.kernel.org/netdev/[email protected]/
References
- https://git.kernel.org/stable/c/002541ef650b742a198e4be363881439bb9d86b4 git.kernel.org
- https://git.kernel.org/stable/c/3f71753935d648082a8279a97d30efe6b85be680 git.kernel.org
- https://git.kernel.org/stable/c/5998da5a8208ae9ad7838ba322bccb2bdcd95e81 git.kernel.org
- https://git.kernel.org/stable/c/67432915145848658149683101104e32f9fd6559 git.kernel.org
- https://git.kernel.org/stable/c/ab6b19f690d89ae4709fba73a3c4a7911f495b7a git.kernel.org
- https://git.kernel.org/stable/c/da664101fb4a0de5cb70d2bae6a650df954df2af git.kernel.org
- https://git.kernel.org/stable/c/eeca93f06df89be5a36305b7b9dae1ed65550dfc git.kernel.org
- https://git.kernel.org/stable/c/f1c170cae285e4b8f61be043bb17addc3d0a14b5 git.kernel.org
- https://cert-portal.siemens.com/productcert/html/ssa-253495.html cert-portal.siemens.com