UBUNTU-CVE-2021-26717

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    UBUNTU-CVE-2021-26717

    Published: 18 Feb 2021Last Modified: 17 Oct 2026
    Upstream:
    CVE-2021-26717

    Summary:

    Details: An issue was discovered in Sangoma Asterisk 16.x before 16.16.1, 17.x before 17.9.2, and 18.x before 18.2.1 and Certified Asterisk before 16.8-cert6. When re-negotiating for T.38, if the initial remote response was delayed just enough, Asterisk would send both audio and T.38 in the SDP. If this happened, and the remote responded with a declined T.38 stream, then Asterisk would crash.

    References: https://ubuntu.com/security/CVE-2021-26717, http://packetstormsecurity.com/files/161471/Asterisk-Project-Security-Advisory-AST-2021-002.html, http://seclists.org/fulldisclosure/2021/Feb/58, https://downloads.asterisk.org/pub/security/, https://downloads.asterisk.org/pub/security/AST-2021-002.html, https://issues.asterisk.org/jira/browse/ASTERISK-29203, https://www.cve.org/CVERecord?id=CVE-2021-26717

    Affected packages

    Package

    Name: asterisk

    Purl: pkg:deb/ubuntu/asterisk?arch=source&distro=jammy

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -None

    Affected versions

    1:16.16.1~dfsg-2
    1:16.16.1~dfsg-4
    1:16.16.1~dfsg-4build1
    1:16.16.1~dfsg+~2.10-1

    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-2021-26717 | CVE-DB