CVE-2026-21806 json
HCL BigFix Service Management was affected with Admin Session Concurrency vulnerability (CVE-2026-21806)
published last mo. modified 26d ago also EUVD-2026-82876
- cvss
- 3.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 9%
- public exploits
- 0
- none known
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.20% chance of exploitation in the next 30 days, higher than 9% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.1 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Affected products
- HCL Software HCL BigFix Service Management
Classification
- Weakness
-
- CWE-557 Concurrency Issues
References
Sources
- CVE List CVE-2026-21806
- NVD CVE-2026-21806
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