Vulnerability · Published Jun 24, 2021 · Assigned by mozilla

CVE-2021-29949

High 7.8

In plain English

A high-severity security flaw in Thunderbird from Mozilla. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)7.8High

Exploit odds (30 days)0.3%top 75.4% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official 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 packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	thunderbird	1:78.10.0-1	DEBIAN-CVE-2021-29949
Debian:13	thunderbird	1:78.10.0-1	DEBIAN-CVE-2021-29949
Debian:14	thunderbird	1:78.10.0-1	DEBIAN-CVE-2021-29949

Affected products (as reported)

Vendor	Product	Versions
Mozilla	Thunderbird	unspecified – before 78.9.1

References

https://www.mozilla.org/security/advisories/mfsa2021-13/ x_refsource_MISC
https://bugzilla.mozilla.org/show_bug.cgi?id=1682101 x_refsource_MISC