Vulnerability-Lookup

CVE-2026-72587 (GCVE-0-2026-72587)

Vulnerability from cvelistv5 – Published: 2026-08-10 10:41 – Updated: 2026-08-10 13:21

Title

Instatic - Cache Poisoning via Unauthenticated Server Island Endpoint

Summary

A cache poisoning vulnerability in CoreBunch/Instatic through 0.0.14 allows an unauthenticated remote attacker to poison the shared process-wide render cache by manipulating the u query parameter of the GET /_instatic/hole/<nodeId> server island endpoint.

Severity

6.1 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-10 13:21 UTC

CWE

CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Assigner

TuranSec redhat root

References

1 reference

URL	Tags
https://github.com/CoreBunch/Instatic	third-party-advisory

Impacted products

1 product

Vendor	Product	Version	CPE status
CoreBunch	Instatic	Affected: 0 , ≤ 0.0.14 (semver)	guessed

Date Public

2026-08-10 10:32

Credits

Komiljon Ayubov

Show details on NVD website

JSON

To clipboard

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FKIE_CVE-2026-72587

Vulnerability from fkie_nvd - Published: 2026-08-10 11:17 - Updated: 2026-08-10 14:17

Severity

6.1 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Summary

References

	URL	Tags
	309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c	https://github.com/CoreBunch/Instatic

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unknown",
          "product": "Instatic",
          "vendor": "CoreBunch",
          "versions": [
            {
              "lessThanOrEqual": "0.0.14",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
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    }
  ],
  "id": "CVE-2026-72587",
  "lastModified": "2026-08-10T14:17:30.267",
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          "integrityImpact": "LOW",
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          "scope": "CHANGED",
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GHSA-9P8F-PPFJ-8GC5

Vulnerability from github – Published: 2026-08-10 12:31 – Updated: 2026-08-10 12:31

Details

Severity

6.1 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-72587"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-444"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-10T11:17:31Z",
    "severity": "MODERATE"
  },
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  "id": "GHSA-9p8f-ppfj-8gc5",
  "modified": "2026-08-10T12:31:53Z",
  "published": "2026-08-10T12:31:53Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72587"
    },
    {
      "type": "WEB",
      "url": "https://github.com/CoreBunch/Instatic"
    }
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      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    }
  ]
}

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.

Action not permitted

CVE-2026-72587 (GCVE-0-2026-72587)

FKIE_CVE-2026-72587

GHSA-9P8F-PPFJ-8GC5

Tags

Sightings

Nomenclature