CVE-2022-23108 in Badge Plugin
Summary
by MITRE • 01/12/2022
Jenkins Badge Plugin 1.9 and earlier does not escape the description and does not check for allowed protocols when creating a badge, resulting in a stored cross-site scripting (XSS) vulnerability exploitable by attackers with Item/Configure permission.
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Analysis
by VulDB Data Team • 01/16/2022
The Jenkins Badge Plugin vulnerability identified as CVE-2022-23108 represents a critical stored cross-site scripting flaw that emerged from inadequate input validation and output escaping mechanisms within the plugin's badge creation functionality. This vulnerability affects versions 1.9 and earlier, where the plugin fails to properly sanitize user-supplied description data and does not validate the protocols used in badge URLs. The flaw specifically resides in the plugin's handling of badge parameters, where description fields are directly rendered without appropriate HTML escaping, creating an environment where malicious scripts can be persisted and executed when the badge is subsequently displayed to users. The vulnerability requires minimal privileges, as attackers only need the Item/Configure permission to exploit it, making it particularly dangerous in environments where multiple users have varying levels of access to Jenkins configuration.
The technical implementation of this vulnerability stems from the plugin's failure to apply proper output encoding when rendering badge descriptions and URL parameters. When users configure badges through the Jenkins interface, the plugin accepts description text and URL values without performing adequate sanitization checks. The absence of protocol validation means that attackers can inject malicious URLs using protocols such as javascript:, data:, or vbscript: that would execute when the badge is rendered in a web browser. This stored XSS vulnerability allows attackers to inject malicious JavaScript code into the badge description field, which gets executed whenever any user views the badge within the Jenkins interface. The vulnerability manifests as a CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') with additional elements of CWE-20: Improper Input Validation, as the plugin fails to validate the inputs before storing them.
The operational impact of this vulnerability extends beyond simple script execution, as it provides attackers with a persistent foothold within the Jenkins environment. Once exploited, the stored XSS allows attackers to steal session cookies, redirect users to malicious sites, or inject additional malicious content into the Jenkins interface. The vulnerability's exploitation capability is particularly concerning because it requires only the Item/Configure permission, which many Jenkins installations grant to developers or build administrators. This means that an attacker with relatively low privileges could compromise the entire Jenkins environment by injecting malicious code into badge descriptions that would execute whenever any user accesses the affected pages. The attack vector operates through standard web browser mechanisms, making it difficult to detect and prevent without proper input validation and output encoding controls.
Mitigation strategies for CVE-2022-23108 should prioritize immediate plugin version updates to 1.10 or later, where the XSS vulnerability has been addressed through proper input sanitization and output escaping. Organizations should implement comprehensive input validation that strips or escapes potentially dangerous characters and protocols from badge description fields. The solution must include protocol validation that rejects non-HTTP/HTTPS URLs to prevent execution of malicious scripts through protocol-based injection. Security teams should also consider implementing content security policies that restrict script execution within the Jenkins interface and conduct regular security audits of plugin configurations. Additionally, privilege management should be reviewed to ensure that only trusted users have Item/Configure permissions, as this reduces the attack surface for this particular vulnerability. The remediation approach aligns with ATT&CK technique T1059.001 for Command and Scripting Interpreter and T1566.001 for Phishing, as the vulnerability enables attackers to establish persistent command execution capabilities through web-based attack vectors. Organizations should also implement monitoring for unusual badge configuration activities and consider implementing automated scanning tools to detect potential XSS payloads in Jenkins configuration data.