CVE-2026-21821: XSS in HCL BigFix SCM Reporting
Platform
javascript
Component
jquery
CVE-2026-21821 identifies a Cross-Site Scripting (XSS) vulnerability within the HCL BigFix SCM Reporting site. This vulnerability arises from the use of an outdated and unsupported version of the jQuery 1.x library. Exploitation could allow attackers to inject malicious scripts, potentially leading to data theft or unauthorized actions. Versions 1.0.0 through 11.0.5 are affected, and a fix is available via upgrading jQuery.
Impact and Attack Scenarios
The presence of an outdated jQuery library in HCL BigFix SCM Reporting creates a significant attack surface. Attackers can leverage publicly known vulnerabilities within jQuery 1.x to execute arbitrary JavaScript code within the context of a user's browser. This could manifest as stealing session cookies, redirecting users to malicious websites, or defacing the reporting site. The impact extends beyond the reporting site itself, as a successful attack could potentially compromise the underlying BigFix infrastructure if user credentials or sensitive data are exposed. The lack of security updates for jQuery 1.x means that newly discovered vulnerabilities will not be patched, increasing the long-term risk.
Exploitation Context
CVE-2026-21821 was published on May 13, 2026. The vulnerability's severity is rated HIGH (CVSS 8.3). As jQuery 1.x is end-of-life, numerous known vulnerabilities exist within the library, making exploitation relatively straightforward. Public proof-of-concept exploits are likely to emerge, increasing the risk of active campaigns. Monitor security advisories from HCL and jQuery for further updates and mitigation guidance.
Threat Intelligence
Exploit Status
CISA SSVC
CVSS Vector
What do these metrics mean?
- Attack Vector
- Network — remotely exploitable over the internet. No physical or local access required. Widest attack surface.
- Attack Complexity
- High — requires a race condition, non-default configuration, or specific circumstances. Harder to exploit reliably.
- Privileges Required
- None — unauthenticated. No login or credentials needed to exploit.
- User Interaction
- Required — victim must take an action: open a file, click a link, or visit a crafted page.
- Scope
- Changed — successful attack can pivot beyond the vulnerable component to other systems or the host OS.
- Confidentiality
- High — complete confidentiality loss. Attacker can read all data: credentials, keys, personal data.
- Integrity
- High — attacker can write, modify, or delete any data: databases, config files, or code.
- Availability
- High — complete crash or resource exhaustion. Full denial of service.
Affected Software
Weakness Classification (CWE)
Timeline
- Reserved
- Published
- Modified
Mitigation and Workarounds
The primary mitigation for CVE-2026-21821 is to upgrade the jQuery library to a supported version. HCL should provide updated versions of BigFix SCM Reporting with a patched jQuery library. If a direct upgrade is not immediately feasible, consider implementing a Content Security Policy (CSP) to restrict the execution of inline scripts and limit the sources from which scripts can be loaded. Furthermore, a Web Application Firewall (WAF) can be configured to filter out malicious JavaScript payloads targeting jQuery functions. Verify the upgrade by testing the reporting site for XSS vulnerabilities after applying the patch.
How to fix
Actualice la biblioteca jQuery a una versión compatible y con soporte. HCL recomienda actualizar a una versión de jQuery que reciba actualizaciones de seguridad y correcciones de errores.
Frequently asked questions
What is CVE-2026-21821 — XSS in HCL BigFix SCM Reporting?
CVE-2026-21821 is a HIGH severity vulnerability affecting HCL BigFix SCM Reporting versions 1.0.0–11.0.5. It's caused by an outdated jQuery library, allowing attackers to inject malicious scripts via Cross-Site Scripting (XSS).
Am I affected by CVE-2026-21821 in HCL BigFix SCM Reporting?
If you are using HCL BigFix SCM Reporting versions between 1.0.0 and 11.0.5, you are potentially affected. Check your jQuery version to confirm.
How do I fix CVE-2026-21821 in HCL BigFix SCM Reporting?
Upgrade to a patched version of HCL BigFix SCM Reporting that includes a supported jQuery version. Implement a Content Security Policy (CSP) as an interim measure.
Is CVE-2026-21821 being actively exploited?
While no active campaigns are currently confirmed, the vulnerability's severity and the age of the jQuery library suggest a high likelihood of exploitation. Monitor security advisories closely.
Where can I find the official HCL advisory for CVE-2026-21821?
Refer to the HCL Support website and security advisories for the latest information and official guidance regarding CVE-2026-21821. Search for 'HCL BigFix SCM Reporting security advisories'.
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