Vulnerability-Lookup

GHSA-6G6Q-GCM9-395J

Vulnerability from github – Published: 2026-04-10 18:31 – Updated: 2026-04-10 18:31

Details

CouchCMS contains a privilege escalation vulnerability that allows authenticated Admin-level users to create SuperAdmin accounts by tampering with the f_k_levels_list parameter in user creation requests. Attackers can modify the parameter value from 4 to 10 in the HTTP request body to bypass authorization validation and gain full application control, circumventing restrictions on SuperAdmin account creation and privilege assignment.

Severity

7.2 (High)


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

8.6 (High)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

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{
  "affected": [],
  "aliases": [
    "CVE-2026-29002"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-639"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-04-10T16:16:30Z",
    "severity": "HIGH"
  },
  "details": "CouchCMS contains a privilege escalation vulnerability that allows authenticated Admin-level users to create SuperAdmin accounts by tampering with the f_k_levels_list parameter in user creation requests. Attackers can modify the parameter value from 4 to 10 in the HTTP request body to bypass authorization validation and gain full application control, circumventing restrictions on SuperAdmin account creation and privilege assignment.",
  "id": "GHSA-6g6q-gcm9-395j",
  "modified": "2026-04-10T18:31:17Z",
  "published": "2026-04-10T18:31:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-29002"
    },
    {
      "type": "WEB",
      "url": "https://gist.github.com/thepiyushkumarshukla/477e2d2bbbe8cc3ec0d640c50f0cf9e1"
    },
    {
      "type": "WEB",
      "url": "https://www.couchcms.com"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/couchcms-privilege-escalation-via-f-k-levels-list-parameter"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-29002 (GCVE-0-2026-29002)

Vulnerability from cvelistv5 – Published: 2026-04-10 15:11 – Updated: 2026-07-14 18:39

Title

CouchCMS Privilege Escalation via f_k_levels_list Parameter

Summary

Severity

8.6 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

7.2 (High)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-10 16:18 UTC

CWE

CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

VulnCheck mitre root Scorecard

References

3 references

URL	Tags
https://gist.github.com/thepiyushkumarshukla/477e…	technical-descriptionexploit
https://www.couchcms.com/	product
https://www.vulncheck.com/advisories/couchcms-pri…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
CouchCMS	CouchCMS	Affected: 0 , ≤ 2.4.0 (semver) cpe:2.3:a:couchcms:couchcms::::::::

Date Public

2026-04-03 00:00

Credits

Piyush Kumar Shukla

Show details on NVD website

JSON

To clipboard

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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.

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.

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Action not permitted

GHSA-6G6Q-GCM9-395J

CVE-2026-29002 (GCVE-0-2026-29002)

Tags

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Nomenclature

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