CVE-2026-93750

http-cache-semantics through 4.2.0 contains a cache validation vulnerability in the _varyMatches() function that fails to properly validate Vary header wildcards due to byte-for-byte string comparison. Attackers can request URLs previously fetched by other clients to receive cached responses intended for different users, disclosing sensitive information across clients.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/kornelski/http-cache-semantics
https://github.com/kornelski/http-cache-semantics/blob/f01112e954b83cfa8765b633ba880e5e980aa54c/index.js#L483-L501
https://github.com/kornelski/http-cache-semantics/issues/57
https://www.vulncheck.com/advisories/http-cache-semantics-through-4.2.0-cross-client-cache-disclosure-via-vary-wildcard
https://github.com/kornelski/http-cache-semantics/issues/57

Configurations

No configuration.

History

18 Sep 2026, 18:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 18:18

Updated : 2026-09-23 17:17

NVD link : CVE-2026-93750

Mitre link : CVE-2026-93750

CVE.ORG link : CVE-2026-93750

JSON object : View

Products Affected

No product.

CWE

CWE-436

Interpretation Conflict

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