USN-4993-1

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    USN-4993-1

    Published: 21 Jun 2021Last Modified: 22 Apr 2026

    Summary: dovecot vulnerabilities

    Details: Kirin discovered that Dovecot incorrectly escaped kid and azp fields in JWT tokens. A local attacker could possibly use this issue to validate tokens using arbitrary keys. This issue only affected Ubuntu 20.10 and Ubuntu 21.04. (CVE-2021-29157) Fabian Ising and Damian Poddebniak discovered that Dovecot incorrectly handled STARTTLS when using the SMTP submission service. A remote attacker could possibly use this issue to inject plaintext commands before STARTTLS negotiation. (CVE-2021-33515)

    References: https://ubuntu.com/security/notices/USN-4993-1, https://ubuntu.com/security/CVE-2021-29157, https://ubuntu.com/security/CVE-2021-33515

    Affected packages

    Package

    Name: dovecot

    Purl: pkg:deb/ubuntu/dovecot@1:2.3.7.2-1ubuntu3.4?arch=source&distro=focal

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 0
    Fixed -1:2.3.7.2-1ubuntu3.4

    Affected versions

    1:2.3.4.1-5ubuntu3
    1:2.3.7.2-1ubuntu1
    1:2.3.7.2-1ubuntu2
    1:2.3.7.2-1ubuntu3
    1:2.3.7.2-1ubuntu3.1
    1:2.3.7.2-1ubuntu3.2
    1:2.3.7.2-1ubuntu3.3

    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
    USN-4993-1 | CVE-DB