CVE-2026-119285

Fiber is an Express inspired web framework written in Go. From 2.52.1 until 2.52.3, the CORS middleware's validateDomain wildcard matcher in middleware/cors/utils.go strips the scheme and checks only a host suffix without requiring a dot boundary. An application configured with a wildcard-subdomain AllowOrigins value and AllowCredentials enabled can reflect an unrelated attacker-controlled origin whose host merely ends with the configured base domain. A user who visits that origin can expose authenticated cross-origin responses to the attacker's page; empty-label origins and later comma-space parsing hardening are outside this advisory. This issue is fixed in version 2.52.3.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/gofiber/fiber/commit/1aac6f618b6bd3e159d2449acb4232a2170b976b
https://github.com/gofiber/fiber/pull/2915
https://github.com/gofiber/fiber/releases/tag/v2.52.3
https://github.com/gofiber/fiber/security/advisories/GHSA-g5jq-qmqr-qrwf

Configurations

No configuration.

History

29 Oct 2026, 22:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-29 22:17

Updated : 2026-10-30 19:37

NVD link : CVE-2026-119285

Mitre link : CVE-2026-119285

CVE.ORG link : CVE-2026-119285

JSON object : View

Products Affected

No product.

CWE

CWE-346

Origin Validation Error

CWE-942

Permissive Cross-domain Security Policy with Untrusted Domains

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