CVE-2026-93750

http-cache-semantics through 4.2.0 Cross-Client Cache Disclosure via Vary Wildcard

At a glance

Severity: HIGH 8.2
EPSS: EPSS 0.45 % · percentile 39 (2026-10-27)
State: PUBLISHED
Published: 2026-09-18
Updated: 2026-09-24
Assigner: VulnCheck
NVD status: Deferred

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.

Scores

Version	Score	Vector	Scored by
CVSS 4.0	HIGH 8.2	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	VulnCheck
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N	VulnCheck
CVSS 4.0	HIGH 8.2	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/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	NVD · disclosure@vulncheck.com (Secondary)
CVSS 3.1	MEDIUM 5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N	NVD · disclosure@vulncheck.com (Primary)

Weaknesses (CWE)

CWE-436

European references

ENISA EUVD · EUVD-2026-83255
GCVE · GCVE-0-2026-93750

CERT-FR advisories

CERTFR-2026-AVI-1378 — Multiples vulnérabilités dans les produits IBM · cert.ssi.gouv.fr

Affected products

Product	Versions
kornelski · http-cache-semantics	affected 0 ≤ 4.2.0

References

Sources

Source	Licence
CVE List (CVEProject cvelistV5)	CVE Program Terms of Use
EPSS (FIRST.org)	FIRST — attribution requested
ENISA EUVD	ENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)	Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feeds	Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD