Security readout for executives and security teams
Plain-English summary
Cisco ISE guest portal management pages improperly validate input, allowing an authenticated administrator to run script in another interface user's browser. Impact is limited by required admin credentials and user interaction, but ISE supports identity infrastructure, so browser-based data exposure matters.
Executive priority
Treat as a near-term infrastructure hygiene item, not an emergency unless ISE admin credentials may be compromised. Prioritize patch planning, administrator access review, and monitoring because ISE is security-critical identity infrastructure.
Technical view
CWE-79 XSS in the web-based management interface of Cisco ISE guest portals. CVSS 3.1 is 4.8: network reachable, low complexity, high privileges required, user interaction required, changed scope, low confidentiality and integrity impact, no availability impact.
Likely exposure
Organizations running Cisco Identity Services Engine Software versions listed as affected, including 3.1, 3.2, 3.3, 3.4, and 3.5 patch trains, should assess exposure. Risk is concentrated where administrative access is broad or poorly monitored.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation. Exploitation requires valid administrative credentials and a user interacting with affected interface content. This is more likely to matter after credential compromise or insider misuse than as an unauthenticated perimeter entry point.
Researcher notes
Evidence supports authenticated XSS only. Do not assume unauthenticated exploitation, code execution on the appliance, or active exploitation from the provided sources. Fix details are not included in the bundle, so remediation should be confirmed against Cisco's advisory.
Mitigation direction
- Check Cisco's advisory for fixed-release or mitigation guidance for your exact ISE version.
- Upgrade or patch affected Cisco ISE deployments according to Cisco-supported guidance.
- Restrict ISE administrative access to trusted administrators and management networks.
- Review administrator accounts and remove unnecessary high-privilege access.
- Increase monitoring for unexpected guest portal configuration changes.
Validation and detection
- Inventory Cisco ISE Software versions and patch levels across all nodes.
- Compare installed versions against the affected version list in the CVE bundle.
- Confirm guest portal management access is limited to authorized administrators.
- Review administrative logs for unusual guest portal edits or unexpected admin sessions.
- After remediation, verify the deployed version is no longer listed as affected.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2025-20204 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 4.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N1.72.7ciscoVulnerability scoring details
Base CVSS 3.1 score
4.8MediumVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- cisco-sa-ise-xss-42tgsdMGCVE reference, cisco
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.