Vulnerability-Lookup

GHSA-RQ97-C8JM-449Q

Vulnerability from github – Published: 2026-09-11 18:31 – Updated: 2026-09-11 18:31

Details

Concrete CMS RSS Displayer block below version 9.5.3 rendered remote feed item titles without HTML escaping, resulting in stored cross-site scripting. An attacker able to control a title in a syndicated feed could execute script in the site origin for any visitor to the affected page, including administrators, without holding an account on that site. The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.0 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks riodrwn for reporting.

Severity

6.0 (Medium)


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

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JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-68528"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-79"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-11T18:16:57Z",
    "severity": "MODERATE"
  },
  "details": "Concrete CMS RSS Displayer block below version 9.5.3  rendered remote feed item titles without HTML escaping, resulting in stored cross-site scripting. An attacker able to control a title in a syndicated feed could execute script in the site origin for any visitor to the affected page, including administrators, without holding an account on that site.\u00a0The Concrete CMS security team gave this vulnerability a CVSS v4.0 score of 6.0 with vector CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N. Thanks riodrwn for reporting.",
  "id": "GHSA-rq97-c8jm-449q",
  "modified": "2026-09-11T18:31:26Z",
  "published": "2026-09-11T18:31:26Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-68528"
    },
    {
      "type": "WEB",
      "url": "https://documentation.concretecms.org/developers/introduction/version-history/953-release-notes"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:H/VI:L/VA:N/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-2026-68528 (GCVE-0-2026-68528)

Vulnerability from cvelistv5 – Published: 2026-09-11 17:34 – Updated: 2026-09-11 19:26

Title

Concrete CMS 9.5.2 and below is vulnerable to Stored XSS in RSS Displayer Block via Unescaped Remote Feed Item title

Summary

Severity

6 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-11 19:26 UTC

CWE

CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Assigner

ConcreteCMS mitre root

References

1 reference

URL	Tags
https://documentation.concretecms.org/developers/…	release-notes

Impacted products

1 product

Vendor	Product	Version
Concrete CMS	Concrete CMS	Affected: 5.0.0 , ≤ 9.5.2 (git)

Credits

riodrwn

Show details on NVD website

JSON

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                "id": "CVE-2026-68528",
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                  },
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                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-11T19:26:33.174720Z",
                "version": "2.0.3"
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        },
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            }
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            {
              "lang": "en",
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        }
      ],
      "metrics": [
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            "attackVector": "NETWORK",
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            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "NONE",
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        "orgId": "ff5b8ace-8b95-4078-9743-eac1ca5451de",
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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.

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.

Action not permitted

GHSA-RQ97-C8JM-449Q

CVE-2026-68528 (GCVE-0-2026-68528)

Tags

Sightings

Nomenclature