CVE-2014-2065 in Jenkins
Summary
by MITRE
Cross-site scripting (XSS) vulnerability in CloudBees Jenkins before 1.551 and LTS before 1.532.2 allows remote attackers to inject arbitrary web script or HTML via the iconSize cookie.
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Analysis
by VulDB Data Team • 03/30/2022
The vulnerability identified as CVE-2014-2065 represents a critical cross-site scripting flaw affecting CloudBees Jenkins versions prior to 1.551 and LTS versions before 1.532.2. This weakness resides in the handling of the iconSize cookie parameter, which fails to properly sanitize user input before incorporating it into web responses. The vulnerability enables remote attackers to execute arbitrary web scripts or HTML code within the context of other users' browsers, potentially leading to unauthorized access, session hijacking, or data exfiltration. The flaw demonstrates a classic XSS vulnerability pattern where unvalidated user-supplied data enters the application's web response without adequate sanitization or encoding mechanisms.
The technical implementation of this vulnerability stems from insufficient input validation and output encoding practices within Jenkins' web interface processing. When the iconSize cookie parameter is processed, the application does not adequately filter or escape special characters that could be interpreted as HTML or JavaScript code. This allows attackers to craft malicious cookie values containing script payloads that get executed when subsequent web pages render. The vulnerability operates under CWE-79 which categorizes improper neutralization of input during web page generation, specifically addressing cross-site scripting flaws. The attack vector requires minimal privileges as it operates through cookie manipulation, making it particularly dangerous in environments where Jenkins serves as a central automation platform with diverse user access levels.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable sophisticated attack chains targeting Jenkins administrators and regular users. An attacker could exploit this flaw to steal session cookies, redirect users to malicious sites, or inject persistent XSS payloads that remain active across multiple sessions. Given that Jenkins is commonly used for continuous integration and deployment workflows, the compromise of a single user's session could potentially provide access to build systems, source code repositories, and deployment credentials. This vulnerability aligns with ATT&CK technique T1531 which focuses on establishing persistence through malicious scripts, and T1059 which covers command and control through scripting languages.
Mitigation strategies for CVE-2014-2065 require immediate patching of affected Jenkins installations to versions 1.551 or LTS 1.532.2 and later. Organizations should also implement comprehensive cookie validation mechanisms and ensure proper output encoding for all user-supplied parameters. Network-level protections including web application firewalls can provide additional defense-in-depth measures, though these should not replace proper application-level fixes. Security teams should conduct thorough vulnerability assessments of their Jenkins environments and review all cookie handling mechanisms for similar XSS vulnerabilities. Regular security auditing of web applications and implementation of automated input validation frameworks can prevent similar issues from emerging in future deployments, as recommended by OWASP Top Ten Project guidelines for preventing cross-site scripting vulnerabilities.