Raw vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:NCVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.
Summary
CVE-2023-23956 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Broadcom Symantec Siteminder Webagent. Its CVSS base score is 5.4 (Medium).
Operationally, exploitation aligns with the MITRE ATT&CK technique Protocol or Service Impersonation (T1001.003); ranked in the top 13% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2023-23956 is a stored cross-site scripting vulnerability (CWE-79) affecting Symantec SiteMinder WebAgent version 12.52. The flaw permits an attacker to supply malicious HTML and JavaScript that executes in the victim's browser, yielding a CVSS 3.1 score of 5.4 under the vector AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
An authenticated user with low privileges can inject the payload over the network; successful exploitation requires the victim to interact with the crafted content and results in limited confidentiality and integrity impacts within a changed security context, allowing actions such as session hijacking or unauthorized actions on behalf of the targeted user.
Broadcom security advisories referenced in the disclosure provide official guidance on available patches and configuration changes to address the issue in supported SiteMinder deployments. Public proof-of-concept material has also been posted to Packet Storm.
The associated EPSS score has remained in a narrow band between 0.0711 and a peak of 0.0818, indicating modest but stable exploitation interest rather than a pronounced post-disclosure increase.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2023-28021
Vulnerability Data
A user can supply malicious HTML and JavaScript code that will be executed in the client browser
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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V1.1.2V1.3.2
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.
Validates web inputs to reject script-related content that could produce XSS.
Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Secure SDLC practices directly target introduction of XSS via coding standards/testing (mostly), yet the single broad outcome leaves many specific neutralization vectors unaddressed (partial).
Patching and EOL replacement can remediate known XSS instances in libraries or frameworks (partial) but do nothing to enforce input neutralization in application code (none).
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
A.5.6 only promotes membership in groups to improve knowledge, receive alerts, and share information; it performs no action that stops XSS exploitation (or even the underlying neutralization defect) and is a pure dependency for other controls per the owner's labeling rule.