Vulnerability-Lookup

GHSA-R72G-8WQ6-6M7W

Vulnerability from github – Published: 2026-09-16 21:32 – Updated: 2026-09-16 21:32

Details

Shlink through 5.1.6 fails to enforce API key role restrictions when issuing Mercure subscription tokens, allowing restricted keys to subscribe to all topics. Attackers with author-only or domain-only keys can access the mercure-info endpoint to receive visit data including referrer, user agent, geolocation, and full short URL objects for URLs outside their authorization boundary.

Severity

6.5 (Medium)


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

7.1 (High)


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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-92760"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-863"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-16T21:17:24Z",
    "severity": "HIGH"
  },
  "details": "Shlink through 5.1.6 fails to enforce API key role restrictions when issuing Mercure subscription tokens, allowing restricted keys to subscribe to all topics. Attackers with author-only or domain-only keys can access the mercure-info endpoint to receive visit data including referrer, user agent, geolocation, and full short URL objects for URLs outside their authorization boundary.",
  "id": "GHSA-r72g-8wq6-6m7w",
  "modified": "2026-09-16T21:32:53Z",
  "published": "2026-09-16T21:32:52Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-92760"
    },
    {
      "type": "WEB",
      "url": "https://github.com/shlinkio/shlink/issues/2633"
    },
    {
      "type": "WEB",
      "url": "https://github.com/shlinkio/shlink"
    },
    {
      "type": "WEB",
      "url": "https://github.com/shlinkio/shlink-common/blob/main/src/Mercure/LcobucciJwtProvider.php#L38-L41"
    },
    {
      "type": "WEB",
      "url": "https://github.com/shlinkio/shlink/blob/v5.1.6/module/Rest/src/Action/MercureInfoAction.php#L26-L42"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/shlink-through-5.1.6-mercure-token-authorization-bypass"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/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-2026-92760 (GCVE-0-2026-92760)

Vulnerability from cvelistv5 – Published: 2026-09-16 20:32 – Updated: 2026-09-17 15:01

Title

Shlink through 5.1.6 Mercure Token Authorization Bypass

Summary

Severity

7.1 (High)


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

6.5 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-17 15:00 UTC

CWE

CWE-863 - Incorrect Authorization

Assigner

VulnCheck mitre root

References

5 references

URL	Tags
https://github.com/shlinkio/shlink/issues/2633	issue-tracking
https://github.com/shlinkio/shlink	product
https://github.com/shlinkio/shlink/blob/v5.1.6/mo…	technical-description
https://github.com/shlinkio/shlink-common/blob/ma…	technical-description
https://www.vulncheck.com/advisories/shlink-throu…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
shlinkio	shlink	Affected: 0 , ≤ 5.1.6 (semver)

Date Public

2026-06-20 00:00

Credits

George Chen

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "adp": [
      {
        "metrics": [
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            "other": {
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                "id": "CVE-2026-92760",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-17T15:00:49.023740Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
          "dateUpdated": "2026-09-17T15:01:06.137Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
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            "url": "https://github.com/shlinkio/shlink/issues/2633"
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        ],
        "title": "CISA ADP Vulnrichment"
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            }
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          "lang": "en",
          "type": "finder",
          "value": "George Chen"
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      "descriptions": [
        {
          "lang": "en",
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        }
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            "privilegesRequired": "LOW",
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          "tags": [
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          "tags": [
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        },
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          ],
          "url": "https://github.com/shlinkio/shlink/blob/v5.1.6/module/Rest/src/Action/MercureInfoAction.php#L26-L42"
        },
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        },
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    "dateReserved": "2026-09-16T19:06:20.161Z",
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  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.