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Status published
Unknown
CVE-2021-43529
Thunderbird versions prior to 91.3.0 are vulnerable to the heap...
Vulnerability Description
Thunderbird versions prior to 91.3.0 are vulnerable to the heap overflow described in CVE-2021-43527 when processing S/MIME messages. Thunderbird versions 91.3.0 and later will not call the vulnerable code when processing S/MIME messages that contain certificates with DER-encoded DSA or RSA-PSS signatures.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
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Affected Vendor
Mozilla
View all reports →Affected Software
Thunderbird
Vulnerable Versions:
unspecified
Timeline
Official Publish:
February 16th, 2023
Last Modified:
March 19th, 2025
Added to House:
July 21st, 2026
CVSS Vectors
No vector data available
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.