Copyright © 2012 Red Hat, Inc. All rights reserved. Moderate 2026-06-26T00:00:00 kernel: net: phonet: do not BUG_ON() in pn_socket_autobind() on failed bind 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CWE-253

In the Linux kernel, the following vulnerability has been resolved: net: phonet: do not BUG_ON() in pn_socket_autobind() on failed bind syzbot reported a kernel BUG triggered from pn_socket_sendmsg() via pn_socket_autobind(): kernel BUG at net/phonet/socket.c:213! RIP: 0010:pn_socket_autobind net/phonet/socket.c:213 [inline] RIP: 0010:pn_socket_sendmsg+0x240/0x250 net/phonet/socket.c:421 Call Trace: sock_sendmsg_nosec+0x112/0x150 net/socket.c:797 __sock_sendmsg net/socket.c:812 [inline] __sys_sendto+0x402/0x590 net/socket.c:2280 ... pn_socket_autobind() calls pn_socket_bind() with port 0 and, on -EINVAL, assumes the socket was already bound and asserts that the port is non-zero: err = pn_socket_bind(sock, ..., sizeof(struct sockaddr_pn)); if (err != -EINVAL) return err; BUG_ON(!pn_port(pn_sk(sock->sk)->sobject)); return 0; /* socket was already bound */ However pn_socket_bind() also returns -EINVAL when sk->sk_state is not TCP_CLOSE, even when the socket has never been bound and pn_port() is still 0. In that case the BUG_ON() fires and panics the kernel from a user-triggerable path. Treat the "bind returned -EINVAL but pn_port() is still 0" case as a regular error and propagate -EINVAL to the caller instead of crashing. Existing callers already translate a non-zero return from pn_socket_autobind() into -ENOBUFS/-EAGAIN, so returning -EINVAL here only changes behaviour from panic to a normal errno.

A flaw was found in the Linux kernel's phonet networking subsystem. A local user could trigger a kernel panic by sending a specially crafted message, leading to a denial of service. This occurs because the `pn_socket_autobind()` function incorrectly assumes a socket is already bound when `pn_socket_bind()` returns an `-EINVAL` error, causing a `BUG_ON()` assertion to fire.

Red Hat Enterprise Linux 10 Not affected kernel Red Hat Enterprise Linux 6 Out of support scope kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Not affected kernel Red Hat Enterprise Linux 8 Not affected kernel-rt Red Hat Enterprise Linux 9 Not affected kernel Red Hat Enterprise Linux 9 Not affected kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-53292 https://nvd.nist.gov/vuln/detail/CVE-2026-53292 https://lore.kernel.org/linux-cve-announce/2026062617-CVE-2026-53292-666f@gregkh/T