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    CVE-2021-23993

    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.

    Published:Apr 8, 2021
    Last Modified:Nov 21, 2024
    EPS:Jun 24, 2021
    EPSS Score:0.00051
    CVSS Score:6.5

    Affected Products

    Vendor
    Mozilla
    Product
    Thunderbird
    Vendor
    Redhat
    Product
    Enterprise Linux
    Vendor
    Redhat
    Product
    Rhel Eus

    Exploits

    No exploit reference

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-463 Padding Oracle Crypto Attack
    CAPEC-475 Signature Spoofing by Improper Validation

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    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High