Vulnerability-Lookup

GHSA-CH52-4W7C-C8XP

Vulnerability from github – Published: 2026-09-18 18:31 – Updated: 2026-09-18 18:31

Details

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.

Severity

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-93748"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-524"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-18T18:18:33Z",
    "severity": "HIGH"
  },
  "details": "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\u0027s Set-Cookie session credentials from shared-cache entries that were deliberately zeroed for security reasons.",
  "id": "GHSA-ch52-4w7c-c8xp",
  "modified": "2026-09-18T18:31:44Z",
  "published": "2026-09-18T18:31:44Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-93748"
    },
    {
      "type": "WEB",
      "url": "https://github.com/kornelski/http-cache-semantics/issues/56"
    },
    {
      "type": "WEB",
      "url": "https://github.com/kornelski/http-cache-semantics"
    },
    {
      "type": "WEB",
      "url": "https://github.com/kornelski/http-cache-semantics/blob/f01112e954b83cfa8765b633ba880e5e980aa54c/index.js#L425-L441"
    },
    {
      "type": "WEB",
      "url": "https://github.com/kornelski/http-cache-semantics/blob/f01112e954b83cfa8765b633ba880e5e980aa54c/index.js#L603-L623"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/http-cache-semantics-through-4.2.0-cross-user-cache-disclosure-via-max-stale"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "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/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",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-93748 (GCVE-0-2026-93748)

Vulnerability from cvelistv5 – Published: 2026-09-18 17:51 – Updated: 2026-09-18 20:05

Title

http-cache-semantics through 4.2.0 Cross-User Cache Disclosure via max-stale

Summary

Severity

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

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-18 20:05 UTC

CWE

CWE-524 - Use of Cache Containing Sensitive Information

Assigner

VulnCheck mitre root

References

5 references

URL	Tags
https://github.com/kornelski/http-cache-semantics…	issue-tracking
https://github.com/kornelski/http-cache-semantics	product
https://github.com/kornelski/http-cache-semantics…	technical-description
https://github.com/kornelski/http-cache-semantics…	technical-description
https://www.vulncheck.com/advisories/http-cache-s…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
kornelski	http-cache-semantics	Affected: 0 , ≤ 4.2.0 (semver) cpe:2.3:a:http-cache-semantics_project:http-cache-semantics::::::::

Date Public

2026-09-17 00:00

Credits

Wayde Shi (PayPal Cyber Security Team)

Show details on NVD website

JSON

To clipboard

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  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-93748",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-18T20:05:06.835112Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
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        "providerMetadata": {
          "dateUpdated": "2026-09-18T20:05:12.650Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
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        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/kornelski/http-cache-semantics/issues/56"
          }
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      }
    ],
    "cna": {
      "affected": [
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          "defaultStatus": "unaffected",
          "packageURL": "pkg:npm/http-cache-semantics",
          "product": "http-cache-semantics",
          "vendor": "kornelski",
          "versions": [
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              "lessThanOrEqual": "4.2.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "cpeApplicability": [
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        }
      ],
      "metrics": [
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            "privilegesRequired": "NONE",
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            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
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          "name": "maxAge() zeroing for shared Set-Cookie and proxy-revalidate responses",
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        {
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          "tags": [
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    "dateReserved": "2026-09-18T16:30:17.085Z",
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    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.