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    CVE-2021-23999

    If a Blob URL was loaded through some unusual user interaction, it could have been loaded by the System Principal and granted additional privileges that should not be granted to web content. This vulnerability affects Firefox ESR < 78.10, Thunderbird < 78.10, and Firefox < 88.

    Published:Apr 19, 2021
    Last Modified:Nov 21, 2024
    EPS:Jun 24, 2021
    EPSS Score:0.00194
    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

    https://bugzilla.mozilla.org/show_bug.cgi?id=1691153https://bugzilla.mozilla.org/show_bug.cgi?id=1691153

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-10 Buffer Overflow via Environment Variables
    CAPEC-120 Double Encoding
    CAPEC-122 Privilege Abuse
    CAPEC-14 Client-side Injection-induced Buffer Overflow
    CAPEC-15 Command Delimiters
    CAPEC-182 Flash Injection
    CAPEC-233 Privilege Escalation
    CAPEC-24 Filter Failure through Buffer Overflow
    CAPEC-267 Leverage Alternate Encoding
    CAPEC-3 Using Leading 'Ghost' Character Sequences to Bypass Input Filters
    CAPEC-41 Using Meta-characters in E-mail Headers to Inject Malicious Payloads
    CAPEC-43 Exploiting Multiple Input Interpretation Layers
    CAPEC-44 Overflow Binary Resource File
    CAPEC-45 Buffer Overflow via Symbolic Links
    CAPEC-46 Overflow Variables and Tags
    CAPEC-47 Buffer Overflow via Parameter Expansion
    CAPEC-52 Embedding NULL Bytes
    CAPEC-53 Postfix, Null Terminate, and Backslash
    CAPEC-58 Restful Privilege Elevation
    CAPEC-6 Argument Injection
    CAPEC-64 Using Slashes and URL Encoding Combined to Bypass Validation Logic
    CAPEC-67 String Format Overflow in syslog()
    CAPEC-7 Blind SQL Injection
    CAPEC-71 Using Unicode Encoding to Bypass Validation Logic
    CAPEC-73 User-Controlled Filename
    CAPEC-78 Using Escaped Slashes in Alternate Encoding
    CAPEC-79 Using Slashes in Alternate Encoding
    CAPEC-8 Buffer Overflow in an API Call
    CAPEC-80 Using UTF-8 Encoding to Bypass Validation Logic
    CAPEC-88 OS Command Injection
    CAPEC-9 Buffer Overflow in Local Command-Line Utilities
    CAPEC-92 Forced Integer Overflow

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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