TI-2026-17536 Aliases CVE-2026-21806 GHSA-6qc5-jgrf-h9g7

HCL BigFix Service Management was affected with Admin Session Concurrency vulnerability (CVE-2026-21806)

MEDIUM 41CWE-557Published 2026-09-18 · Updated 2026-09-18

Key facts

Attack vector: Network
Privileges required: None
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 · NVD. Fix status from CNA.

Summary

HCL BigFix Service Management is affected by an Administrative Session Concurrency vulnerability. The application allows multiple simultaneous authenticated sessions for the same administrative account, which could enable an unauthorized attacker to predict or hijack valid session identifiers. Successful exploitation allows an attacker to compromise affected administrative sessions and execute actions with full privileged user permissions.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00199 9th 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: Partial

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
HCL Software	HCL BigFix Service Management	Version 27	—	No fix listed	CNA

HCL BigFix Service Management VendorHCL Software Affected Version 27 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:hcltech:bigfix_service_management:27:-::::::	27	Vulnerable	HCL Software

cpe:2.3:a:hcltech:bigfix_service_management:27:-:*:*:*:*:*:* Versions 27 Vulnerable ·HCL Software

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2026-21806
2026-10-03 Alias added: GHSA-6qc5-jgrf-h9g7
2026-10-15 CVSS score added · NVD
2026-10-15 Priority changed: LOW → MEDIUM

References

Advisory 1

https://support.hcl-software.com/csm?id=kb_article&sysparm_article=KB0133592

TI-2026-47494 HCL BigFix Service Management is affected by multiple security vulnerabilities. CVSS 3.1CRITICAL 9.8
TI-2026-40821 HCL BigFix Service Management is affected by multiple security vulnerabilities. CVSS 3.1CRITICAL 9.8
TI-2026-47495 HCL BigFix Service Management is affected by multiple security vulnerabilities. CVSS 3.1CRITICAL 9.3
TI-2026-40820 HCL BigFix Service Management is affected by multiple security vulnerabilities. CVSS 3.1CRITICAL 9.8
TI-2025-23103 HCL BigFix Service Management (SM) is susceptible to a Configuration – 'Insecure Use of… CVSS 3.1CRITICAL 9.8
TI-2025-32693 HCL BigFix Service Management (SM) is affected by use of a vulnerable component CVSS 3.1HIGH 8.8

See all 35 →

Sources

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