CVE-2021-29949

HIGH
7.8
CVSS Score
Published: June 24, 2021 at 01:18 PM UTC
Updated: June 17, 2026 at 03:48 AM UTC
1 product affected across 1 vendorThunderbird

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Severity
HIGH7.8
Exploit prediction
EPSS 0.3%

Description

When loading the shared library that provides the OTR protocol implementation, Thunderbird will initially attempt to open it using a filename that isn't distributed by Thunderbird. If a computer has already been infected with a malicious library of the alternative filename, and the malicious library has been copied to a directory that is contained in the search path for executable libraries, then Thunderbird will load the incorrect library. This vulnerability affects Thunderbird < 78.9.1.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 78.9.1
Affected range stops below 78.9.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

x_refsource_MISCPermissions RequiredVendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1682101
x_refsource_MISCRelease NotesVendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-13/

CVSS

Attack Vector
LOCAL
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-427

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