CVE-2021-44538

Severity Score

9.8

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

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.

La función olm_session_describe en Matrix libolm versiones anteriores a 3.2.7, es vulnerable a un desbordamiento de búfer. El objeto Olm session representa un canal criptográfico entre dos partes. Por lo tanto, su estado es parcialmente controlable por la parte remota del canal. Los atacantes pueden construir una secuencia de mensajes manipulada para manipular el estado de la sesión del receptor de tal manera que, para algunos tamaños de búfer, se produzca un desbordamiento de búfer en una llamada a olm_session_describe. Además, los tamaños de búfer seguros no estaban documentados. El contenido del desbordamiento es parcialmente controlable por el atacante y se limita a espacios y dígitos ASCII. Los productos afectados conocidos son Element Web y SchildiChat Web

*Credits: N/A

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

Partial

Integrity

Partial

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2021-12-03 CVE Reserved
2021-12-14 CVE Published
2024-08-04 CVE Updated
2024-08-29 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer

CAPEC

References (4)

URL	Tag	Source
https://gitlab.matrix.org/matrix-org/olm/-/tags	Product
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html	Mailing List

URL	Date	SRC

URL	Date	SRC
https://matrix.org/blog/2021/12/13/disclosure-buffer-overflow-in-libolm-and-matrix-js-sdk	2023-08-08

URL	Date	SRC
https://www.debian.org/security/2022/dsa-5034	2023-08-08

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Matrix Search vendor "Matrix"		Element Search vendor "Matrix" for product "Element"				< 1.9.7 Search vendor "Matrix" for product "Element" and version " < 1.9.7"		desktop		Affected
Matrix Search vendor "Matrix"		Element Search vendor "Matrix" for product "Element"				< 1.9.7 Search vendor "Matrix" for product "Element" and version " < 1.9.7"		web		Affected
Matrix Search vendor "Matrix"		Javascript Sdk Search vendor "Matrix" for product "Javascript Sdk"				>= 2.4.2 < 15.2.1 Search vendor "Matrix" for product "Javascript Sdk" and version " >= 2.4.2 < 15.2.1"		-		Affected
Matrix Search vendor "Matrix"		Olm Search vendor "Matrix" for product "Olm"				>= 3.1.4 < 3.2.8 Search vendor "Matrix" for product "Olm" and version " >= 3.1.4 < 3.2.8"		-		Affected
Schildi Search vendor "Schildi"		Schildichat Search vendor "Schildi" for product "Schildichat"				< 1.9.7-sc1 Search vendor "Schildi" for product "Schildichat" and version " < 1.9.7-sc1"		desktop		Affected
Schildi Search vendor "Schildi"		Schildichat Search vendor "Schildi" for product "Schildichat"				< 1.9.7-sc1 Search vendor "Schildi" for product "Schildichat" and version " < 1.9.7-sc1"		web		Affected
Cinny Project Search vendor "Cinny Project"		Cinny Search vendor "Cinny Project" for product "Cinny"				< 1.6.0 Search vendor "Cinny Project" for product "Cinny" and version " < 1.6.0"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				10.0 Search vendor "Debian" for product "Debian Linux" and version "10.0"		-		Affected
Debian Search vendor "Debian"		Debian Linux Search vendor "Debian" for product "Debian Linux"				11.0 Search vendor "Debian" for product "Debian Linux" and version "11.0"		-		Affected