CVE-2026-20309

MEDIUMPre-NVD 6.16.1—
EchelonGraph scoreHIGH confidence

Score 6.1 from GitHub Security Advisory published 2026-09-16. a secondary CVSS source baseline 6.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
6.1EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 6.1Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

A vulnerability in the web-based management interface of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to conduct a reflected cross-site scripting (XSS) attack against a user of the interface. This vulnerability exists because the web-based management interface does not properly validate user-supplied input. An attacker could exploit this vulnerability by persuading a user of the interface to click a crafted link. A successful exploit could allow the attacker to execute arbitrary script code in the context of the affected interface or access sensitive, browser-based information.

CVSS v3
6.1
EG Score
6.1(high)
EG Risk
28(Track)
EG Risk 28/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity61% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
9%
KEV
Not listed

Published

September 16, 2026

Last Modified

September 18, 2026

Advisory Details (1)

Auto-updated Sep 16, 2026
No patch confirmed yet.
generic

Cisco Identity Services Engine Cross-Site Scripting Vulnerability

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ise-xss-Uz9VWRQ

Vendor Advisories for CVE-2026-20309(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 11× in last 7d / 11× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-09-19 11:38 UTCEG score recompute
  2. 2026-09-19 11:38 UTCGHSA enrichment
  3. 2026-09-18 19:27 UTCEPSS rescore
  4. 2026-09-18 13:41 UTCGHSA enrichment
  5. 2026-09-18 12:16 UTCEG score recompute
  6. 2026-09-18 12:16 UTCGHSA enrichment
  7. 2026-09-17 14:19 UTCEG score recompute
  8. 2026-09-17 14:19 UTCGHSA enrichment
  9. 2026-09-16 21:26 UTCEG score recompute
  10. 2026-09-16 20:34 UTCEG score recompute
  11. 2026-09-16 20:29 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-20309?
CVE-2026-20309 is a medium vulnerability published on September 16, 2026. A vulnerability in the web-based management interface of Cisco Identity Services Engine (ISE) could allow an unauthenticated, remote attacker to conduct a reflected cross-site scripting (XSS) attack against a user of the interface. This vulnerability exists because the web-based management…
When was CVE-2026-20309 disclosed?
CVE-2026-20309 was first published in the National Vulnerability Database on September 16, 2026, with the most recent update on September 18, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-20309 actively exploited?
CVE-2026-20309 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 90.7% of all scored CVEs.
What is the CVSS score of CVE-2026-20309?
CVE-2026-20309 has a CVSS v3 base score of 6.1 (NVD).
How do I remediate CVE-2026-20309?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-20309, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-20309

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