UBUNTU-CVE-2021-3449

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    UBUNTU-CVE-2021-3449

    Published: 25 Mar 2021Last Modified: 22 May 2026
    Upstream:
    CVE-2021-3449

    Summary:

    Details: An OpenSSL TLS server may crash if sent a maliciously crafted renegotiation ClientHello message from a client. If a TLSv1.2 renegotiation ClientHello omits the signature_algorithms extension (where it was present in the initial ClientHello), but includes a signature_algorithms_cert extension then a NULL pointer dereference will result, leading to a crash and a denial of service attack. A server is only vulnerable if it has TLSv1.2 and renegotiation enabled (which is the default configuration). OpenSSL TLS clients are not impacted by this issue. All OpenSSL 1.1.1 versions are affected by this issue. Users of these versions should upgrade to OpenSSL 1.1.1k. OpenSSL 1.0.2 is not impacted by this issue. Fixed in OpenSSL 1.1.1k (Affected 1.1.1-1.1.1j).

    References: https://ubuntu.com/security/CVE-2021-3449, https://www.openssl.org/news/secadv/20210325.txt, https://ubuntu.com/security/notices/USN-4891-1, https://ubuntu.com/security/notices/USN-5038-1, https://github.com/nodejs/node/pull/38083, https://www.cve.org/CVERecord?id=CVE-2021-3449

    Affected packages

    Package

    Name: openssl

    Purl: pkg:deb/ubuntu/openssl?arch=source&distro=bionic

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -1.1.1-1ubuntu2.1~18.04.9

    Affected versions

    1.0.2g-1ubuntu13
    1.0.2g-1ubuntu14
    1.0.2n-1ubuntu1

    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-2021-3449 | CVE-DB