CVE-2026-64004high

net/iucv: fix locking in .getsockopt

21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.8epss 0.1%

exploitation probability

0.1%top 97% of all CVEs

observed exploitation

nono source reports it

In the Linux kernel, the following vulnerability has been resolved: net/iucv: fix locking in .getsockopt Mirror iucv_sock_setsockopt() and wrap the whole switch in lock_sock()/release_sock(). The pre-existing SO_MSGLIMIT-only lock becomes redundant and is removed. Any AF_IUCV HIPER user can potentially crash the kernel by racing recvmsg() with getsockopt(SO_MSGSIZE): the SO_MSGSIZE arm dereferences iucv->hs_dev->mtu after iucv_sock_close() (called from the racing recvmsg()) has set hs_dev to NULL, producing a NULL pointer dereference oops.

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

Linux · Linux

References

https://git.kernel.org/stable/c/1fc30bd4e55e2dd622d2d366cecd732c1841bbee https://git.kernel.org/stable/c/3589d20a666caf30ad100c960a2de7de390fce88 https://git.kernel.org/stable/c/45bb8de8c95d8899f4b8f61bd9bceb8132af73cb https://git.kernel.org/stable/c/69554adc7a6fa04ede3ad7512321d83748e3c920 https://git.kernel.org/stable/c/6e792b8dd3002bbc4136745928a9605df1a72b8a https://git.kernel.org/stable/c/884eb247b74d86db97e3a37f0d6fc8e1e83590dd https://git.kernel.org/stable/c/9817369243380e287ebe5525411557eaa3aa2a79 https://git.kernel.org/stable/c/cd691beafea0dd779e69e81ccc26b0ab50efcb5e