UBUNTU-CVE-2021-41816

    Dashboard / Vulnerabilities / UBUNTU-CVE-2021-41816

    UBUNTU-CVE-2021-41816

    Published: 2 Dec 2021Last Modified: 22 Apr 2026
    Upstream:
    CVE-2021-41816
    Aliases:
    USN-5235-1

    Summary:

    Details: CGI.escape_html in Ruby before 2.7.5 and 3.x before 3.0.3 has an integer overflow and resultant buffer overflow via a long string on platforms (such as Windows) where size_t and long have different numbers of bytes. This also affects the CGI gem before 0.3.1 for Ruby.

    References: https://ubuntu.com/security/CVE-2021-41816, https://www.ruby-lang.org/en/news/2021/11/24/buffer-overrun-in-cgi-escape_html-cve-2021-41816/, https://github.com/ruby/cgi/commit/c728632c1c09d46cfd4ecbff9caaa3651dd1002a, https://ubuntu.com/security/notices/USN-5235-1, https://www.cve.org/CVERecord?id=CVE-2021-41816

    Affected packages

    Package

    Name: ruby2.7

    Purl: pkg:deb/ubuntu/[email protected]?arch=source&distro=focal

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -2.7.0-5ubuntu1.6

    Affected versions

    2.7.0-1
    2.7.0-2
    2.7.0-3
    2.7.0-4
    2.7.0-4ubuntu1
    2.7.0-5ubuntu1
    2.7.0-5ubuntu1.1
    2.7.0-5ubuntu1.2
    2.7.0-5ubuntu1.3
    2.7.0-5ubuntu1.4
    2.7.0-5ubuntu1.5

    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
    UBUNTU-CVE-2021-41816 | CVE-DB