CVE-2021-34813
CRITICAL
9.8
CVSS Score
Published: June 16, 2021 at 05:11 PM UTC
Updated: June 17, 2026 at 03:56 AM UTC
1 product affected across 1 vendorOlm
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Severity
CRITICAL9.8
Exploit prediction
EPSS 4%
Description
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.
Remediation
No guide yetNo remediation guidance has been written for this CVE yet. What the record does show:
References (3)
x_refsource_MISCPatchVendor Advisory
Source: [email protected]
https://gitlab.matrix.org/matrix-org/olm/-/commit/ccc0d122ee1b4d5e5ca4ec1432086be17d5f901bx_refsource_MISCRelease NotesVendor Advisory
Source: [email protected]
https://gitlab.matrix.org/matrix-org/olm/-/releases/3.2.3x_refsource_MISCExploitPatchVendor Advisory
Source: [email protected]
https://matrix.org/blog/2021/06/14/adventures-in-fuzzing-libolmCVSS
- Attack Vector
- NETWORK
- Complexity
- LOW
- Privileges
- NONE
- User Interaction
- NONE
- Scope
- UNCHANGED
- Confidentiality
- HIGH
- Integrity
- HIGH
- Availability
- HIGH
Vector?
Quick Info
StatusMODIFIED
CWE
CWE-787
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