CVE-2026-93784

What the bug is

The KASAN allocation trace shows that a malformed IE buffer is stored via SIOCSIWGENIE (cfg80211_wext_siwgenie()) without any validation. The crash trace shows that a subsequent SIOCSIWESSID triggers a connection attempt which calls cfg80211_sme_get_conn_ies() to process the stored IE buffer, causing: - An out-of-bounds read in skip_ie() which reads ies[pos+1] (the length byte) past the end of the 1-byte buffer. - An integer underflow in the memcpy size argument when offs returned by ieee80211_ie_split() exceeds ies_len, causing unsigned subtraction to wrap to SIZE_MAX and triggering a fortify panic. Fix this by validating the IE buffer in cfg80211_wext_siwgenie() before storing it. [drop unnecessary ie_len check, update commit message]

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/wireless/wext-sme.c

What this is

802.11 (including CFG80211/NL80211)MAINTAINERS section matched on net/wireless/ · linux-wireless@vger.kernel.org · Maintained

Kernel module

cfg80211

Check it on the machine

grep -wE 'CONFIG_CFG80211|CONFIG_CFG80211_WEXT|CONFIG_WIRELESS' /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 cfg80211

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, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.

• bookwormMnot built on amd64/cloud-amd64, arm64/cloud-arm64
• trixie, forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64, s390x/s390x
• bookworm · linux-6.12Mnot built on amd64/cloud-amd64, arm64/cloud-arm64

M

a module where it is built at all; some flavours do not build it

Build switches

CONFIG_CFG80211, CONFIG_CFG80211_WEXT, CONFIG_WIRELESS

Reads as

all on means the file is compiled; any one off means it is not.

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

2026-09-24 (24 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.17%, higher than 6.2% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

net/wireless

Upstream fixes

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

Introduced	Fixed in	Commit
2.6.32	5.10.271	269498ce6c1e
2.6.32	5.15.222	685082f4be77
2.6.32	6.1.189	8b921a899346
2.6.32	6.6.158	d01f1600e8b0
2.6.32	6.12.111	c970879e03b2
2.6.32	6.18.53	01cc395cecfa
2.6.32	7.2	a2f5286ca4f3

Debian advisories