CVE-2026-93748
http-cache-semantics through 4.2.0 Cross-User Cache Disclosure via max-stale
http-cache-semantics through 4.2.0 fails to properly validate security-zeroed cache entries when processing client max-stale directives, allowing unauthenticated attackers to retrieve cached responses belonging to other users. Attackers can request the same URL with a large max-stale value to obtain another user's Set-Cookie session credentials from shared-cache entries that were deliberately zeroed for security reasons.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| http-cache-semantics kornelski http-cache-semantics
npm |
≥ 0; ≤ 4.2.0 (affected, semver)
Other versions: unaffected |
CNA: VulnCheck |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 8.7 high |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N | CNA: VulnCheck |
| 3.1 / 7.5 high |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N | CNA: VulnCheck |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://github.com/kornelski/http-cache-semantics/issues/56CNA: VulnCheck · issue-tracking
- https://github.com/kornelski/http-cache-semanticsCNA: VulnCheck · product
- https://github.com/kornelski/http-cache-semantics/blob/f01112e954b83cfa8765b633ba880e5e980aa54c/index.js#L425-L441CNA: VulnCheck · technical-description
- https://github.com/kornelski/http-cache-semantics/blob/f01112e954b83cfa8765b633ba880e5e980aa54c/index.js#L603-L623CNA: VulnCheck · technical-description
- https://www.vulncheck.com/advisories/http-cache-semantics-through-4.2.0-cross-user-cache-disclosure-via-max-staleCNA: VulnCheck · third-party-advisory
- https://github.com/kornelski/http-cache-semantics/issues/56#issuecomment-5975759591ADP: CVE
- https://github.com/advisories/GHSA-ch52-4w7c-c8xpADP: CVE
- https://github.com/github/advisory-database/issues/10139ADP: CVE
- https://github.com/advisories/GHSA-ch52-4w7c-c8xpOSV / GitHub Security Advisories · advisory
- https://osv.dev/vulnerability/GHSA-ch52-4w7c-c8xpOSV / GitHub Security Advisories · osv
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