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[MFSA-2021-36] Security Vulnerabilities fixed in Thunderbird 91

Severity High
Affected Packages 1
Fixed Packages 1
CVEs 9
Info Packages References Vulnerabilities

In general, these flaws cannot be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but are potentially risks in browser or browser-like contexts.

  • CVE-2021-29980: Uninitialized memory in a canvas object could have led to memory corruption (high)
    Uninitialized memory in a canvas object could have caused an incorrect free() leading to memory corruption and a potentially exploitable crash.

  • CVE-2021-29981: Live range splitting could have led to conflicting assignments in the JIT (high)
    An issue present in lowering/register allocation could have led to obscure but deterministic register confusion failures in JITted code that would lead to a potentially exploitable crash.

  • CVE-2021-29982: Single bit data leak due to incorrect JIT optimization and type confusion (low)
    Due to incorrect JIT optimization, we incorrectly interpreted data from the wrong type of object, resulting in the potential leak of a single bit of memory.

  • CVE-2021-29984: Incorrect instruction reordering during JIT optimization (high)
    Instruction reordering resulted in a sequence of instructions that would cause an object to be incorrectly considered during garbage collection. This led to memory corruption and a potentially exploitable crash.

  • CVE-2021-29985: Use-after-free media channels (moderate)
    A use-after-free vulnerability in media channels could have led to memory corruption and a potentially exploitable crash.

  • CVE-2021-29986: Race condition when resolving DNS names could have led to memory corruption (high)
    A suspected race condition when calling <code>getaddrinfo</code> led to memory corruption and a potentially exploitable crash.
    Note: This issue only affected Linux operating systems. Other operating systems are unaffected.

  • CVE-2021-29987: Users could have been tricked into accepting unwanted permissions on Linux (moderate)
    After requesting multiple permissions, and closing the first permission panel, subsequent permission panels will be displayed in a different position but still record a click in the default location, making it possible to trick a user into accepting a permission they did not want to.
    This bug only affects Thunderbird on Linux. Other operating systems are unaffected.

  • CVE-2021-29988: Memory corruption as a result of incorrect style treatment (high)
    Thunderbird incorrectly treated an inline list-item element as a block element, resulting in an out of bounds read or memory corruption, and a potentially exploitable crash.

  • CVE-2021-29989: Memory safety bugs fixed in Thunderbird 91 (high)
    Mozilla developers Kershaw Chang, Philipp, Chris Peterson, Sebastian Hengst, Christoph Kerschbaumer, Olli Pettay, Sandor Molnar, and Simon Giesecke reported memory safety bugs present in versions of Thunderbird prior to 91. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code.

Package Affected Version
pkg:mozilla/Thunderbird < 91
Package Fixed Version
pkg:mozilla/Thunderbird = 91
ID
MFSA-2021-36
Severity
high
URL
https://www.mozilla.org/en-US/security/advisories/mfsa2021-36
Published
2021-08-11T00:00:00
(3 years ago)
Modified
2021-08-11T00:00:00
(3 years ago)
Other Advisories
Source # ID Name URL
Bugzilla 1722204 https://bugzilla.mozilla.org/show_bug.cgi?id=1722204
Bugzilla 1707774 https://bugzilla.mozilla.org/show_bug.cgi?id=1707774
Bugzilla 1715318 https://bugzilla.mozilla.org/show_bug.cgi?id=1715318
Bugzilla 1720031 https://bugzilla.mozilla.org/show_bug.cgi?id=1720031
Bugzilla 1722083 https://bugzilla.mozilla.org/show_bug.cgi?id=1722083
Bugzilla 1696138 https://bugzilla.mozilla.org/show_bug.cgi?id=1696138
Bugzilla 1716129 https://bugzilla.mozilla.org/show_bug.cgi?id=1716129
Bugzilla 1717922 https://bugzilla.mozilla.org/show_bug.cgi?id=1717922
Bugzilla 1662676 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1662676
Bugzilla 1666184 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1666184
Bugzilla 1719178 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1719178
Bugzilla 1719998 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1719998
Bugzilla 1720568 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1720568
Bugzilla 1544190 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1544190
Bugzilla 1716481 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1716481
Bugzilla 1717778 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1717778
Bugzilla 1719319 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1719319
Bugzilla 1722073 Memory safety bugs fixed in Thunderbird 91 https://bugzilla.mozilla.org/show_bug.cgi?id=1722073
Type Package URL Namespace Name / Product Version Distribution / Platform Arch Patch / Fix
Affected pkg:mozilla/Thunderbird Thunderbird < 91
Fixed pkg:mozilla/Thunderbird Thunderbird = 91
# CVE Description CVSS EPSS EPSS Trend (30 days) Affected Products Weaknesses Security Advisories Exploits PoC Pubblication Date Modification Date
# CVE Description CVSS EPSS EPSS Trend (30 days) Affected Products Weaknesses Security Advisories PoC Pubblication Date Modification Date