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CVE

CVE-2026-27818

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

CVE-2026-27818

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

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.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
8.7
-
4.0
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/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
C
H
U
0
-
C
H
U
-

Related Resources

No items found.

References

https://github.com/TerriaJS/terriajs-server/security/advisories/GHSA-w789-49fc-v8hr, https://nvd.nist.gov/vuln/detail/CVE-2026-27818, https://github.com/TerriaJS/terriajs-server/commit/3aaa5d9717162b245ae4569232bbe7d8673c913f, https://github.com/TerriaJS/terriajs-server, https://github.com/TerriaJS/terriajs-server/releases/tag/4.0.3

Severity

7.5

CVSS Score
0
10

Basic Information

Ecosystem
Base CVSS
7.5
EPSS Probability
0.00089%
EPSS Percentile
0.25067%
Introduced Version
0
Fix Available
4.0.3

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