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.
History

Wed, 23 Sep 2026 00:15:00 +0000

Type Values Removed Values Added
Weaknesses CWE-524
References
Metrics threat_severity

None

threat_severity

Moderate


Mon, 21 Sep 2026 10:45:00 +0000

Type Values Removed Values Added
First Time appeared Kornelski
Kornelski http-cache-semantics
Vendors & Products Kornelski
Kornelski http-cache-semantics

Fri, 18 Sep 2026 21:30:00 +0000

Type Values Removed Values Added
Description 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.
Title http-cache-semantics through 4.2.0 Cross-Client Cache Disclosure via Vary Wildcard
First Time appeared Http-cache-semantics Project
Http-cache-semantics Project http-cache-semantics
Weaknesses CWE-436
CPEs cpe:2.3:a:http-cache-semantics_project:http-cache-semantics:*:*:*:*:*:*:*:*
Vendors & Products Http-cache-semantics Project
Http-cache-semantics Project http-cache-semantics
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N'}

cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-09-18T17:51:35.687Z

Updated: 2026-09-24T14:23:09.209Z

Reserved: 2026-09-18T16:30:17.776Z

Link: CVE-2026-93750

cve-icon Vulnrichment

Updated: 2026-09-18T18:03:16.325Z

cve-icon NVD

Status : Deferred

Published: 2026-09-18T18:18:33.633

Modified: 2026-09-23T17:17:49.997

Link: CVE-2026-93750

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-09-18T17:51:35Z

Links: CVE-2026-93750 - Bugzilla