Description

Improper neutralization of input in Apache Roller 6.1.5 allows an anonymous remote attacker to store a crafted comment-author URL that can execute script in the session of a weblog moderator or global administrator when the comment management page is viewed. This affects sites that permit comments on at least one weblog and whose moderator subsequently reviews the submitted comment; no non-default server setting is required. Users are recommended to upgrade to Apache Roller 6.1.6 or later.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.1",
  "pubDate": "2026-09-28T09:17:07.520Z",
  "pubdate": "2026-09-28T09:17:07.520Z",
  "executiveSummary": "This vulnerability is classified as a Stored Cross-Site Scripting (XSS) flaw within Apache Roller version 6.1.5. It arises from improper neutralization of user-supplied input provided via the comment-author URL field.\nThe vulnerability allows an unauthenticated remote attacker to inject malicious scripts into the comment metadata. The impact is significant, as the payload executes within the context of a privileged user's session—specifically a weblog moderator or a global administrator—when they access the comment management interface to review submitted comments.\nSuccessful exploitation compromises the integrity and confidentiality of the administrative session, potentially leading to unauthorized administrative actions, session hijacking, or exfiltration of sensitive session tokens. The attack does not require any non-default server configurations, making any instance of Apache Roller 6.1.5 that permits weblog comments inherently vulnerable.\nRemediation requires an immediate upgrade to Apache Roller version 6.1.6 or later, which contains the necessary input sanitization and output encoding fixes to prevent the execution of arbitrary scripts injected through comment parameters.",
  "technicalDetails": "The vulnerability resides in the comment submission mechanism of Apache Roller 6.1.5. The application fails to adequately sanitize the 'url' parameter provided by commenters before storing it in the persistent database. Because the application logic does not perform server-side input validation or context-aware output encoding on this field, it allows for the injection of arbitrary HTML and JavaScript payloads.\nThe attack flow begins when an anonymous remote attacker submits a comment to a weblog, providing a crafted malicious URI in the author's URL field. This string, containing an XSS payload (e.g., <script>alert(document.cookie)</script> or an equivalent obfuscated vector), is processed and persisted by the Apache Roller backend.\nThe vulnerability manifests during the administrative workflow. When a weblog moderator or a global administrator navigates to the administrative comment management console, the application retrieves the stored comment data to display it for review. The browser renders the malicious string as part of the management interface's DOM. Because the application fails to properly escape the stored metadata before rendering, the browser interprets the injected payload as executable script.\nThe execution occurs within the security context of the logged-in administrator. Since the script runs in an active, authenticated session, it gains the ability to execute actions on behalf of the administrator, such as modifying blog settings, deleting content, or performing unauthorized administrative operations. Furthermore, the script can access document objects, facilitating session token theft through cookie manipulation or by capturing keystrokes and administrative credentials.\nThis vulnerability specifically impacts Apache Roller 6.1.5. The root cause is a failure in the input/output lifecycle management where user-supplied URL data is treated as trusted content. As there is no requirement for elevated privileges to submit the malicious comment, the attack surface is exposed to any remote actor capable of interacting with the comment submission form on any enabled weblog. The lack of Content Security Policy (CSP) enforcement on the administrative panel likely exacerbates the potential for successful exploitation by failing to restrict the sources or types of scripts that can be executed."
}