TI-2026-16429 Aliases CVE-2026-20237 GHSA-8h74-5vrg-hj96

Cisco Identity Services Engine Hardening Release - Input Validation Vulnerabilities

MEDIUM 42CWE-20Published 2026-09-16 · Updated 2026-09-18

Key facts

Attack vector: Network
Privileges required: High
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Identity Services Engine (ISE) and Cisco ISE Passive Identity Connector (ISE-PIC), engineering teams have conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20237 are related to improper input validation issues that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-20.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00478 41st percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Cisco	Cisco Identity Services Engine Software	3.1.0; 3.1.0 p1; 3.1.0 p3; 3.1.0 p2; 3.2.0; 3.1.0 p4; 3.1.0 p5; 3.2.0 p1; 3.1.0 p6; 3.2.0 p2; 3.1.0 p7; 3.3.0; 3.2.0 p3; 3.2.0 p4; 3.1.0 p8; 3.2.0 p5; 3.2.0 p6; 3.1.0 p9; 3.3 Patch 2; 3.3 Patch 1; 3.3 Patch 3; 3.4.0; 3.2.0 p7; 3.3 Patch 4; 3.4 Patch 1; 3.1.0 p10; 3.3 Patch 5; 3.3 Patch 6; 3.4 Patch 2; 3.3 Patch 7; 3.4 Patch 3; 3.5.0; 3.4 Patch 4; 3.3 Patch 8; 3.2 Patch 8; 3.5 Patch 1; 3.3 Patch 9; 3.2 Patch 9; 3.4 Patch 5; 3.5 Patch 3; 3.5 Patch 2; 3.3 Patch 10; 3.3 Patch 11; 3.4 Patch 6; 3.2 Patch 10; 3.1.0 p72; 3.1.0 p11	—	No fix listed	CNA
Cisco	Cisco ISE Passive Identity Connector	3.2.0; 3.1.0; 3.3.0; 3.4.0; 3.5.0	—	No fix listed	CNA

Cisco Identity Services Engine Software VendorCisco Affected 3.1.0; 3.1.0 p1; 3.1.0 p3; 3.1.0 p2; 3.2.0; 3.1.0 p4; 3.1.0 p5; 3.2.0 p1; 3.1.0 p6; 3.2.0 p2; 3.1.0 p7; 3.3.0; 3.2.0 p3; 3.2.0 p4; 3.1.0 p8; 3.2.0 p5; 3.2.0 p6; 3.1.0 p9; 3.3 Patch 2; 3.3 Patch 1; 3.3 Patch 3; 3.4.0; 3.2.0 p7; 3.3 Patch 4; 3.4 Patch 1; 3.1.0 p10; 3.3 Patch 5; 3.3 Patch 6; 3.4 Patch 2; 3.3 Patch 7; 3.4 Patch 3; 3.5.0; 3.4 Patch 4; 3.3 Patch 8; 3.2 Patch 8; 3.5 Patch 1; 3.3 Patch 9; 3.2 Patch 9; 3.4 Patch 5; 3.5 Patch 3; 3.5 Patch 2; 3.3 Patch 10; 3.3 Patch 11; 3.4 Patch 6; 3.2 Patch 10; 3.1.0 p72; 3.1.0 p11 Fixed in — No fix listed CNA
Cisco ISE Passive Identity Connector VendorCisco Affected 3.2.0; 3.1.0; 3.3.0; 3.4.0; 3.5.0 Fixed in — No fix listed CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPE	Versions	Role	Vendor
cpe:2.3:a:cisco:identity_services_engine::::::::	—	—	Cisco

cpe:2.3:a:cisco:identity_services_engine:*:*:*:*:*:*:*:* Versions — — ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-20237
2026-10-03 Alias added: GHSA-8h74-5vrg-hj96

References

Other 1

cisco-sa-hardening-ise-XU5EwX5T

TI-2026-74174 Arbitrary file write in Cisco Secure Email Gateway via AMP feature KEVCVSS 3.1CRITICAL 9.8
TI-2026-53490 Cisco Catalyst SD-WAN Manager System Account Authorization Bypass Vulnerability KEVCVSS 3.1CRITICAL 9.8
TI-2026-53489 Cisco Secure Email Gateway SQL Injection Vulnerability KEVCVSS 3.1CRITICAL 9.8
TI-2026-53488 Cisco Identity Services Engine Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 10.0
TI-2026-16388 Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 10.0
TI-2026-16344 Cisco Secure Firewall Management Center Software Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0

See all 7059 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences