CVE-2025-37756

Summary

In the Linux kernel, the following vulnerability has been resolved: net: tls: explicitly disallow disconnect syzbot discovered that it can disconnect a TLS socket and then run into all sort of unexpected corner cases. I have a vague recollection of Eric pointing this out to us a long time ago. Supporting disconnect is really hard, for one thing if offload is enabled we'd need to wait for all packets to be _acked_. Disconnect is not commonly used, disallow it. The immediate problem syzbot run into is the warning in the strp, but that's just the easiest bug to trigger: WARNING: CPU: 0 PID: 5834 at net/tls/tls_strp.c:486 tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486 RIP: 0010:tls_strp_msg_load+0x72e/0xa80 net/tls/tls_strp.c:486 Call Trace: <TASK> tls_rx_rec_wait+0x280/0xa60 net/tls/tls_sw.c:1363 tls_sw_recvmsg+0x85c/0x1c30 net/tls/tls_sw.c:2043 inet6_recvmsg+0x2c9/0x730 net/ipv6/af_inet6.c:678 sock_recvmsg_nosec net/socket.c:1023 [inline] sock_recvmsg+0x109/0x280 net/socket.c:1045 __sys_recvfrom+0x202/0x380 net/socket.c:2237

Impact & exploitability

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

Affected products we track (2)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Official patch: https://git.kernel.org/stable/c/2bcad8fefcecdd5f005d8c550b25d703c063c34a ↗

Additional information

• NVD record
• https://git.kernel.org/stable/c/2bcad8fefcecdd5f005d8c550b25d703c063c34aPatch
• https://git.kernel.org/stable/c/5071a1e606b30c0c11278d3c6620cd6a24724cf6Patch
• https://git.kernel.org/stable/c/7bdcf5bc35ae59fc4a0fa23276e84b4d1534a3cfPatch
• https://git.kernel.org/stable/c/8513411ec321942bd3cfed53d5bb700665c67d86Patch
• https://git.kernel.org/stable/c/9fcbca0f801580cbb583e9cb274e2c7fbe766ca6Patch
• https://git.kernel.org/stable/c/ac91c6125468be720eafde9c973994cb45b61d44Patch
• https://git.kernel.org/stable/c/c665bef891e8972e1d3ce5bbc0d42a373346a2c3Patch
• https://git.kernel.org/stable/c/f3ce4d3f874ab7919edca364c147ac735f9f1d04Patch