In the Linux kernel, the following vulnerability has been resolved: tls: handle data disappearing from under the TLS ULP TLS expects that it owns the receive queue of the TCP socket. This cannot be guaranteed in case the reader of the TCP socket entered before the TLS ULP was installed, or uses some non-standard read API (eg. zerocopy ones). Replace the WARN_ON() and a buggy early exit (which leaves anchor pointing to a freed skb) with real error handling. Wipe the parsing state and tell the reader to retry. We already reload the anchor every time we (re)acquire the socket lock, so the only condition we need to avoid is an out of bounds read (not having enough bytes in the socket for previously parsed record len). If some data was read from under TLS but there's enough in the queue we'll reload and decrypt what is most likely not a valid TLS record. Leading to some undefined behavior from TLS perspective (corrupting a stream? missing an alert? missing an attack?) but no kernel crash should take place.
History

Sat, 23 Aug 2025 11:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Vendors & Products Linux
Linux linux Kernel

Sat, 23 Aug 2025 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-366
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Fri, 22 Aug 2025 13:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: tls: handle data disappearing from under the TLS ULP TLS expects that it owns the receive queue of the TCP socket. This cannot be guaranteed in case the reader of the TCP socket entered before the TLS ULP was installed, or uses some non-standard read API (eg. zerocopy ones). Replace the WARN_ON() and a buggy early exit (which leaves anchor pointing to a freed skb) with real error handling. Wipe the parsing state and tell the reader to retry. We already reload the anchor every time we (re)acquire the socket lock, so the only condition we need to avoid is an out of bounds read (not having enough bytes in the socket for previously parsed record len). If some data was read from under TLS but there's enough in the queue we'll reload and decrypt what is most likely not a valid TLS record. Leading to some undefined behavior from TLS perspective (corrupting a stream? missing an alert? missing an attack?) but no kernel crash should take place.
Title tls: handle data disappearing from under the TLS ULP
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2025-08-22T13:01:23.217Z

Updated: 2025-08-22T13:01:23.217Z

Reserved: 2025-04-16T04:51:24.029Z

Link: CVE-2025-38616

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-08-22T14:15:46.017

Modified: 2025-08-22T18:08:51.663

Link: CVE-2025-38616

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-08-22T00:00:00Z

Links: CVE-2025-38616 - Bugzilla