CVE-2021-34813

Matrix libolm before 3.2.3 allows a malicious Matrix homeserver to crash a client (while it is attempting to retrieve an Olm encrypted room key backup from the homeserver) because olm_pk_decrypt has a stack-based buffer overflow. Remote code execution might be possible for some nonstandard build configurations.

CVSS v3.0 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

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CVSS v3.0 : CRITICAL

V3 Legend

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

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CVSS v2.0 : HIGH

V2 Legend

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://gitlab.matrix.org/matrix-org/olm/-/releases/3.2.3	Release Notes Vendor Advisory
https://matrix.org/blog/2021/06/14/adventures-in-fuzzing-libolm	Exploit Patch Vendor Advisory
https://gitlab.matrix.org/matrix-org/olm/-/commit/ccc0d122ee1b4d5e5ca4ec1432086be17d5f901b	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:matrix:olm:*:*:*:*:*:*:*:*

Information

Published : 2021-06-16 11:15

Updated : 2021-06-23 07:29

NVD link : CVE-2021-34813

Mitre link : CVE-2021-34813

JSON object : View

CWE

CWE-787

Out-of-bounds Write

Products Affected

matrix

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