Vulnerability-Lookup

GHSA-W789-49FC-V8HR

Vulnerability from github – Published: 2026-02-26 15:22 – Updated: 2026-02-26 15:22

Summary

TerriaJS-Server has a domain validation bypass vulnerability in its proxy allowlist

Details

Impact

A validation bug allows an attacker to proxy domains not explicitly allowed in the proxyableDomains configuration.

The validation only checks if a hostname ended with an allowed domain. This meant:

If example.com is allowed in proxyableDomains:

✅ example.com is allowed (correct)
✅ api.example.com is allowed (correct)
⚠️ maliciousexample.com is allowed (incorrect)

An attacker could register maliciousexample.com and proxy content through terriajs-server, bypassing proxy restrictions.

Patches

All versions up to 4.0.2 are affected. Upgrade to 4.0.3 to address the vulnerability.

Severity

8.7 (High)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "terriajs-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "4.0.3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-27818"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-20",
      "CWE-918"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-02-26T15:22:11Z",
    "nvd_published_at": "2026-02-26T00:16:26Z",
    "severity": "HIGH"
  },
  "details": "### Impact\nA validation bug allows an attacker to proxy domains not explicitly allowed in the `proxyableDomains` configuration.\n\nThe validation only checks if a hostname _ended_ with an allowed domain. This meant:\n\nIf `example.com` is allowed in `proxyableDomains`:\n\n- \u2705 example.com is allowed (correct)\n- \u2705 api.example.com is allowed (correct)\n- \u26a0\ufe0f maliciousexample.com is allowed (incorrect)\n\nAn attacker could register maliciousexample.com and proxy content through `terriajs-server`, bypassing proxy restrictions.\n\n### Patches\nAll versions up to 4.0.2 are affected. Upgrade to 4.0.3 to address the vulnerability.",
  "id": "GHSA-w789-49fc-v8hr",
  "modified": "2026-02-26T15:22:11Z",
  "published": "2026-02-26T15:22:11Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/TerriaJS/terriajs-server/security/advisories/GHSA-w789-49fc-v8hr"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-27818"
    },
    {
      "type": "WEB",
      "url": "https://github.com/TerriaJS/terriajs-server/commit/3aaa5d9717162b245ae4569232bbe7d8673c913f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/TerriaJS/terriajs-server"
    },
    {
      "type": "WEB",
      "url": "https://github.com/TerriaJS/terriajs-server/releases/tag/4.0.3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "TerriaJS-Server has a domain validation bypass vulnerability in its proxy allowlist"
}

CVE-2026-27818 (GCVE-0-2026-27818)

Vulnerability from cvelistv5 – Published: 2026-02-26 00:02 – Updated: 2026-02-26 15:16

Title

TerriaJS-Server has a domain validation bypass vulnerability in its proxy allowlist

Summary

TerriaJS-Server is a NodeJS Express server for TerriaJS, a library for building web-based geospatial data explorers. A validation bug in versions prior to 4.0.3 allows an attacker to proxy domains not explicitly allowed in the `proxyableDomains` configuration. Version 4.0.3 fixes the issue.

Severity

8.7 (High)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-02-26 15:16 UTC

CWE

CWE-20 - Improper Input Validation
CWE-918 - Server-Side Request Forgery (SSRF)

Assigner

GitHub_M mitre root Scorecard

References

2 references

URL	Tags
https://github.com/TerriaJS/terriajs-server/secur…	x_refsource_CONFIRM
https://github.com/TerriaJS/terriajs-server/commi…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
TerriaJS	terriajs-server	Affected: < 4.0.3

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-27818",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-02-26T15:16:18.815543Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-02-26T15:16:30.580Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "terriajs-server",
          "vendor": "TerriaJS",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 4.0.3"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "TerriaJS-Server is a NodeJS Express server for TerriaJS, a library for building web-based geospatial data explorers. A validation bug in versions prior to 4.0.3 allows an attacker to proxy domains not explicitly allowed in the `proxyableDomains` configuration. Version 4.0.3 fixes the issue."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-20",
              "description": "CWE-20: Improper Input Validation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-918",
              "description": "CWE-918: Server-Side Request Forgery (SSRF)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-26T00:02:45.127Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/TerriaJS/terriajs-server/security/advisories/GHSA-w789-49fc-v8hr",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/TerriaJS/terriajs-server/security/advisories/GHSA-w789-49fc-v8hr"
        },
        {
          "name": "https://github.com/TerriaJS/terriajs-server/commit/3aaa5d9717162b245ae4569232bbe7d8673c913f",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/TerriaJS/terriajs-server/commit/3aaa5d9717162b245ae4569232bbe7d8673c913f"
        }
      ],
      "source": {
        "advisory": "GHSA-w789-49fc-v8hr",
        "discovery": "UNKNOWN"
      },
      "title": "TerriaJS-Server has a domain validation bypass vulnerability in its proxy allowlist"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-27818",
    "datePublished": "2026-02-26T00:02:45.127Z",
    "dateReserved": "2026-02-24T02:32:39.799Z",
    "dateUpdated": "2026-02-26T15:16:30.580Z",
    "state": "PUBLISHED"
  },
  "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.

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.

Action not permitted