CVE-2026-80904

What the bug is

When an async decrypt fails, tls_decrypt_done() records the error in ctx->async_wait.err and calls tls_err_abort(), which stores it in sk_err. tls_sw_recvmsg() and tls_sw_read_sock() each read async_wait.err once they hold the reader lock and fail the call: a record that did not authenticate breaks the connection. tls_sw_splice_read() has no such check, and sk_err does not stand in for one. tls_rx_rec_wait() tests sk_err only inside the loop it skips whenever a record is already parsed, and the first reader to reach sock_error() clears it, while async_wait.err persists. A splice therefore keeps delivering records on a connection that recvmsg() and read_sock() refuse to read. Read async_wait.err in tls_sw_splice_read() as the other two readers do.

Where it lives

The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.

net/tls/tls_sw.c

What this is

NETWORKING [TLS]MAINTAINERS section matched on net/tls/ · netdev@vger.kernel.org · Maintained

Kernel module

tls

Check it on the machine

grep -w CONFIG_TLS /boot/config-$(uname -r)

Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.

lsmod | grep -w tls

Prints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.

Show whether Debian builds this, per release

Debian builds this as a loadable module. Every release below compiles it as a module on every flavour, so whether the code is in the running kernel depends on whether that module is loaded.

• bookworm, trixie, forky, sid, bookworm · linux-6.12m

m

a loadable module on every flavour - check lsmod, can be blacklisted

Build switch

CONFIG_TLS

From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages

Signals

Published

2026-09-04 (44 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.16%, higher than 4.9% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

net/tls

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
5.19	6.1.184	a808aadff634
5.19	6.6.153	06c2a53604fa
5.19	6.12.105	18ae1e95f208
5.19	6.18.46	82d9269f01eb
5.19	7.1.10	4b177911eb9f
5.19	7.2	976df67f463d

Debian advisories