Jenkins CAS Plugin 1.6.0 and earlier improperly determines that a redirect URL after login is legitimately pointing to Jenkins, allowing attackers to perform phishing attacks.

There are packages installed that are affected by a vulnerability referenced in the following CVE:

  - Jenkins CAS Plugin 1.6.0 and earlier improperly determines that a redirect URL after login is legitimately
    pointing to Jenkins, allowing attackers to perform phishing attacks. (CVE-2021-21673)

According to its its self-reported version number, the version of Jenkins running on the remote web server is Jenkins LTS prior to 2.289.2 or Jenkins weekly prior to 2.300. It is, therefore, affected by multiple vulnerabilities:

  - Jenkins 2.299 and earlier, LTS 2.289.1 and earlier allows users to cancel queue items and abort builds of     jobs for which they have Item/Cancel permission even when they do not have Item/Read permission. Jenkins     2.300, LTS 2.289.2 requires that users have Item/Read permission for applicable types in addition to     Item/Cancel permission. As a workaround on earlier versions of Jenkins, do not grant Item/Cancel     permission to users who do not have Item/Read permission. (CVE-2021-21670)

  - Jenkins 2.299 and earlier, LTS 2.289.1 and earlier does not invalidate the existing session on login. This     allows attackers to use social engineering techniques to gain administrator access to Jenkins. This     vulnerability was introduced in Jenkins 2.266 and LTS 2.277.1. Jenkins 2.300, LTS 2.289.2 invalidates the     existing session on login. Note In case of problems, administrators can choose a different implementation     by setting the Java system property hudson.security.SecurityRealm.sessionFixationProtectionMode to 2, or     disable the fix entirely by setting that system property to 0. (CVE-2021-21671)

  - Selenium HTML report Plugin 1.0 and earlier does not configure its XML parser to prevent XML external     entity (XXE) attacks. This allows attackers with the ability to control the report files parsed using this     plugin to have Jenkins parse a crafted report file that uses external entities for extraction of secrets     from the Jenkins controller or server-side request forgery. Selenium HTML report Plugin 1.1 disables     external entity resolution for its XML parser. (CVE-2021-21672)

  - CAS Plugin 1.6.0 and earlier improperly determines that a redirect URL after login is legitimately     pointing to Jenkins. This allows attackers to perform phishing attacks by having users go to a Jenkins URL     that will forward them to a different site after successful authentication. CAS Plugin 1.6.1 only     redirects to relative (Jenkins) URLs. (CVE-2021-21673)

  - requests-plugin Plugin 2.2.6 and earlier does not perform a permission check in an HTTP endpoint. This     allows attackers with Overall/Read permission to view the list of pending requests. requests-plugin Plugin     2.2.7 requires Overall/Read permission to view the list of pending requests. (CVE-2021-21674)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
409115	SCA: security update for org.jenkins-ci.plugins:cas-plugin (GHSA-2vvr-5757-qp87)	Tenable Cloud Security	SCA Checks	Local	medium
409115	SCA: security update for org.jenkins-ci.plugins:cas-plugin (GHSA-2vvr-5757-qp87)	Tenable Self-Hosted Container Security	SCA Checks	Local	medium
151193	Jenkins LTS < 2.289.2 / Jenkins weekly < 2.300 Multiple Vulnerabilities	Nessus	CGI abuses	Combined	high

Detections

Analytics

CVE-2021-21673

medium

Tenable Plugins

medium

medium

high