cbcvebase.
CVE-2021-44538
published 2021-12-14

CVE-2021-44538: The olm_session_describe function in Matrix libolm before 3.2.7 is vulnerable to a buffer overflow. The Olm session object represents a cryptographic channel…

PriorityP349critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
1.92%
77.4th percentile
The olm_session_describe function in Matrix libolm before 3.2.7 is vulnerable to a buffer overflow. The Olm session object represents a cryptographic channel between two parties. Therefore, its state is partially controllable by the remote party of the channel. Attackers can construct a crafted sequence of messages to manipulate the state of the receiver's session in such a way that, for some buffer sizes, a buffer overflow happens on a call to olm_session_describe. Furthermore, safe buffer sizes were undocumented. The overflow content is partially controllable by the attacker and limited to ASCII spaces and digits. The known affected products are Element Web And SchildiChat Web.

Affected

20 ranges
VendorProductVersion rangeFixed in
cinny_projectcinny< 1.6.01.6.0
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianolm< olm 3.2.8~dfsg-1 (bookworm)olm 3.2.8~dfsg-1 (bookworm)
debianthunderbird< olm 3.2.8~dfsg-1 (bookworm)olm 3.2.8~dfsg-1 (bookworm)
matrixelement< 1.9.71.9.7
matrixjavascript_sdk>= 2.4.2 < 15.2.115.2.1
matrixolm>= 0 < 3.2.8~dfsg-13.2.8~dfsg-1
matrixolm>= 0 < 3.2.8~dfsg-13.2.8~dfsg-1
matrixolm>= 0 < 3.2.8~dfsg-13.2.8~dfsg-1
matrixolm>= 3.1.4 < 3.2.83.2.8
mozillafirefox
mozillathunderbird>= 0 < 1:91.4.1-1~deb11u11:91.4.1-1~deb11u1
mozillathunderbird>= 0 < 1:91.4.1-11:91.4.1-1
mozillathunderbird>= 0 < 1:91.4.1-11:91.4.1-1
mozillathunderbird>= 0 < 1:91.4.1-11:91.4.1-1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.18.04.11:91.5.0+build1-0ubuntu0.18.04.1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.20.04.11:91.5.0+build1-0ubuntu0.20.04.1
schildischildichat< 1.9.7-sc11.9.7-sc1

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_ubuntu8.8HIGH
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.