UBUNTU-CVE-2021-26691

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    UBUNTU-CVE-2021-26691

    Published: 10 Jun 2021Last Modified: 22 Apr 2026
    Upstream:
    CVE-2021-26691

    Summary:

    Details: In Apache HTTP Server versions 2.4.0 to 2.4.46 a specially crafted SessionHeader sent by an origin server could cause a heap overflow

    References: https://ubuntu.com/security/CVE-2021-26691, https://httpd.apache.org/security/vulnerabilities_24.html#CVE-2021-26691, https://lists.apache.org/thread.html/r50cae1b71f1e7421069036b213c26da7d8f47dd59874e3bd956959fe@%3Cannounce.httpd.apache.org%3E, http://www.openwall.com/lists/oss-security/2021/06/10/7, https://ubuntu.com/security/notices/USN-4994-1, https://ubuntu.com/security/notices/USN-4994-2, https://www.cve.org/CVERecord?id=CVE-2021-26691

    Affected packages

    Package

    Name: apache2

    Purl: pkg:deb/ubuntu/[email protected]+esm1?arch=source&distro=trusty/esm

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -2.4.7-1ubuntu4.22+esm1

    Affected versions

    2.4.6-2ubuntu2
    2.4.6-2ubuntu3
    2.4.6-2ubuntu4
    2.4.7-1ubuntu1
    2.4.7-1ubuntu2
    2.4.7-1ubuntu3
    2.4.7-1ubuntu4
    2.4.7-1ubuntu4.1
    2.4.7-1ubuntu4.4
    2.4.7-1ubuntu4.5
    2.4.7-1ubuntu4.6
    2.4.7-1ubuntu4.7
    2.4.7-1ubuntu4.8
    2.4.7-1ubuntu4.9
    2.4.7-1ubuntu4.10
    2.4.7-1ubuntu4.11
    2.4.7-1ubuntu4.13
    2.4.7-1ubuntu4.15
    2.4.7-1ubuntu4.16
    2.4.7-1ubuntu4.17
    2.4.7-1ubuntu4.18
    2.4.7-1ubuntu4.19
    2.4.7-1ubuntu4.20
    2.4.7-1ubuntu4.21
    2.4.7-1ubuntu4.22

    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-2021-26691 | CVE-DB