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VULNERABILITIES

CVE-2021-23993 Details

Description

An attacker may perform a DoS attack to prevent a user from sending encrypted email to a correspondent. If an attacker creates a crafted OpenPGP key with a subkey that has an invalid self signature, and the Thunderbird user imports the crafted key, then Thunderbird may try to use the invalid subkey, but the RNP library rejects it from being used, causing encryption to fail. This vulnerability affects Thunderbird < 78.9.1.

Metrics

CVSS 3.x Severity and Vector Strings:

NIST: [email protected]CVSS-B:6.5 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

References to Advisories, Solutions, and Tools

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URLSource(s)Tag(s)
https://bugzilla.mozilla.org/show_bug.cgi?id=1666360 CVEIssue TrackingPermissions RequiredVendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-13/ CVERelease NotesVendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1666360 [email protected]Issue TrackingPermissions RequiredVendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-13/ [email protected]Release NotesVendor Advisory

Weakness Enumeration

CWE-IDCWE NameSource
CWE-347Improper Verification of Cryptographic Signature[email protected]

Affected Products

ProductVersions
mozilla thunderbird
< 78.9.1

CPE

  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.

Change History

5 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2021-23993
NVD Published Date:
Jun 24, 2021
NVD Last Modified:
Jun 17, 2026
Source:
[email protected]