{"id":"DEBIAN-CVE-2025-21670","details":"In the Linux kernel, the following vulnerability has been resolved:  vsock/bpf: return early if transport is not assigned  Some of the core functions can only be called if the transport has been assigned.  As Michal reported, a socket might have the transport at NULL, for example after a failed connect(), causing the following trace:      BUG: kernel NULL pointer dereference, address: 00000000000000a0     #PF: supervisor read access in kernel mode     #PF: error_code(0x0000) - not-present page     PGD 12faf8067 P4D 12faf8067 PUD 113670067 PMD 0     Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI     CPU: 15 UID: 0 PID: 1198 Comm: a.out Not tainted 6.13.0-rc2+     RIP: 0010:vsock_connectible_has_data+0x1f/0x40     Call Trace:      vsock_bpf_recvmsg+0xca/0x5e0      sock_recvmsg+0xb9/0xc0      __sys_recvfrom+0xb3/0x130      __x64_sys_recvfrom+0x20/0x30      do_syscall_64+0x93/0x180      entry_SYSCALL_64_after_hwframe+0x76/0x7e  So we need to check the `vsk-\u003etransport` in vsock_bpf_recvmsg(), especially for connected sockets (stream/seqpacket) as we already do in __vsock_connectible_recvmsg().","modified":"2026-09-01T20:05:42.005379568Z","published":"2025-01-31T12:15:28.160Z","upstream":["CVE-2025-21670"],"references":[{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-21670"}],"affected":[{"package":{"name":"linux","ecosystem":"Debian:13","purl":"pkg:deb/debian/linux?arch=source&distro=trixie"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21670.json"}},{"package":{"name":"linux","ecosystem":"Debian:14","purl":"pkg:deb/debian/linux?arch=source&distro=forky"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.12.11-1"}]}],"ecosystem_specific":{"urgency":"not yet assigned"},"database_specific":{"source":"https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2025-21670.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"}]}