Vulnerability-Lookup

CVE-2026-21806 (GCVE-0-2026-21806)

Vulnerability from cvelistv5 – Published: 2026-09-18 11:12 – Updated: 2026-09-18 11:12

Title

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

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.

Severity

3.1 (Low)


                        
                          CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

CWE

CWE-557 - Concurrency Issues

Assigner

HCL mitre root

References

1 reference

URL	Tags
https://support.hcl-software.com/csm?id=kb_articl…

Impacted products

1 product

Vendor	Product	Version	CPE status
HCL Software	HCL BigFix Service Management	Affected: Version 27	guessed

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JSON

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      "affected": [
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          "defaultStatus": "unaffected",
          "product": "HCL BigFix  Service Management",
          "vendor": "HCL Software",
          "versions": [
            {
              "status": "affected",
              "version": "Version 27"
            }
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        }
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      "metrics": [
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          "cvssV3_1": {
            "attackComplexity": "HIGH",
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            "confidentialityImpact": "LOW",
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        "orgId": "1e47fe04-f25f-42fa-b674-36de2c5e3cfc",
        "shortName": "HCL"
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          "url": "https://support.hcl-software.com/csm?id=kb_article\u0026sysparm_article=KB0133592"
        }
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    "datePublished": "2026-09-18T11:12:24.764Z",
    "dateReserved": "2026-01-05T16:08:06.682Z",
    "dateUpdated": "2026-09-18T11:12:24.764Z",
    "state": "PUBLISHED"
  },
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                  }
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          }
        ],
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        "lastModified": "2026-09-18T13:44:57.517",
        "metrics": {
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          }
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GHSA-6QC5-JGRF-H9G7

Vulnerability from github – Published: 2026-09-18 12:31 – Updated: 2026-09-18 12:31

Details

Severity

3.1 (Low)


                  
                    CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-21806"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-18T12:17:24Z",
    "severity": "LOW"
  },
  "details": "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.",
  "id": "GHSA-6qc5-jgrf-h9g7",
  "modified": "2026-09-18T12:31:20Z",
  "published": "2026-09-18T12:31:20Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-21806"
    },
    {
      "type": "WEB",
      "url": "https://support.hcl-software.com/csm?id=kb_article\u0026sysparm_article=KB0133592"
    }
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  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.