In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack: defer invalid log until after unlock TCP and SCTP conntrack paths can emit invalid-packet logs while ct->lock is still held. When invalid logging is routed to nfnetlink_log and conntrack export is enabled, the log path can re-enter conntrack netlink glue and dump the same conntrack again. Protocol attribute dumping may take ct->lock, so logging while holding that lock can deadlock. Defer the TCP invalid logs by storing only the minimal log context while ct->lock is held and emitting the log after unlocking. Also make the TCP timeout-lowering invalid path return whether a log is needed, then emit that log after unlocking. Do the same for the SCTP invalid state-transition log that can be reached while ct->lock is held. Add a lockdep assertion to nf_ct_l4proto_log_invalid() so future callers that log invalid conntracks while holding ct->lock are caught outside TCP and SCTP as well.
History

Sat, 22 Aug 2026 17:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-1338

Sat, 22 Aug 2026 15:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_conntrack: defer invalid log until after unlock TCP and SCTP conntrack paths can emit invalid-packet logs while ct->lock is still held. When invalid logging is routed to nfnetlink_log and conntrack export is enabled, the log path can re-enter conntrack netlink glue and dump the same conntrack again. Protocol attribute dumping may take ct->lock, so logging while holding that lock can deadlock. Defer the TCP invalid logs by storing only the minimal log context while ct->lock is held and emitting the log after unlocking. Also make the TCP timeout-lowering invalid path return whether a log is needed, then emit that log after unlocking. Do the same for the SCTP invalid state-transition log that can be reached while ct->lock is held. Add a lockdep assertion to nf_ct_l4proto_log_invalid() so future callers that log invalid conntracks while holding ct->lock are caught outside TCP and SCTP as well.
Title netfilter: nf_conntrack: defer invalid log until after unlock
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-08-22T15:32:07.193Z

Reserved: 2026-08-15T05:44:03.921Z

Link: CVE-2026-74624

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-22T16:16:35.280

Modified: 2026-08-22T16:16:35.280

Link: CVE-2026-74624

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-22T19:00:14Z