by Kastro
Paper/Archive/CVE-2026-21806

CVE-2026-21806

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

EPSS 0.2%CVSS 9.8
critical.is priorityof 100
31
CVSS 9.8 (NVD)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 9.7.097 × 201.9No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
HCL BigFix Service ManagementVersion 27–CNA

Scores by source

NVD9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
HCL (CNA)3.1CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: partial

References

refsupport.hcl-software.com/csm?id=kb_article&sysparm_article=KB0133592