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    CVE-2021-29976

    Mozilla developers reported memory safety bugs present in code shared between Firefox and Thunderbird. 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. This vulnerability affects Thunderbird < 78.12, Firefox ESR < 78.12, and Firefox < 90.

    Published:Jul 13, 2021
    Last Modified:Nov 21, 2024
    EPS:Aug 5, 2021
    EPSS Score:0.006
    CVSS Score:8.8

    Affected Products

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

    Exploits

    No exploit reference

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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