CVE-2025-71381

Hono before 4.10.2 (fixed in 4.10.3) contains a flaw in its CORS middleware: when the origin is not set to "*", the middleware copies the Vary header from the incoming request into the response. Because Vary is a response header that should be managed by the server, an attacker can supply arbitrary Vary values that are reflected into the response, potentially causing cache key pollution and inconsistent CORS enforcement in environments that rely on shared caches or proxies.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/honojs/hono/security/advisories/GHSA-q7jf-gf43-6x6p
https://www.vulncheck.com/advisories/hono-vary-header-injection-in-cors-middleware

Configurations

No configuration.

History

30 Jun 2026, 23:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-30 23:16

Updated : 2026-07-02 17:48

NVD link : CVE-2025-71381

Mitre link : CVE-2025-71381

CVE.ORG link : CVE-2025-71381

JSON object : View

Products Affected

No product.

CWE

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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