Vulnerability · Published Aug 5, 2021 · Assigned by mozilla

CVE-2021-29969

Medium 5.9

In plain English

A medium-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 1.2% (higher than 68% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)5.9Medium

Exploit odds (30 days)1.2%top 31.7% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

If Thunderbird was configured to use STARTTLS for an IMAP connection, and an attacker injected IMAP server responses prior to the completion of the STARTTLS handshake, then Thunderbird didn't ignore the injected data. This could have resulted in Thunderbird showing incorrect information, for example the attacker could have tricked Thunderbird to show folders that didn't exist on the IMAP server. This vulnerability affects Thunderbird < 78.12.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Alpine:v3.20	thunderbird	91.3.2-r0	ALPINE-CVE-2021-29969
Alpine:v3.21	thunderbird	91.3.2-r0	ALPINE-CVE-2021-29969
Alpine:v3.22	thunderbird	91.3.2-r0	ALPINE-CVE-2021-29969
Alpine:v3.23	thunderbird	91.3.2-r0	ALPINE-CVE-2021-29969
Debian:12	thunderbird	1:78.12.0-1	DEBIAN-CVE-2021-29969
Debian:13	thunderbird	1:78.12.0-1	DEBIAN-CVE-2021-29969
Debian:14	thunderbird	1:78.12.0-1	DEBIAN-CVE-2021-29969
Rocky Linux:8	thunderbird	0:78.12.0-3.el8_4	RLSA-2021:2883

Affected products (as reported)

Vendor	Product	Versions
Mozilla	Thunderbird	unspecified – before 78.12

References

https://www.mozilla.org/security/advisories/mfsa2021-30/ x_refsource_MISC
https://bugzilla.mozilla.org/show_bug.cgi?id=1682370 x_refsource_MISC
GLSA-202208-14 vendor-advisory, x_refsource_GENTOO