Vulnerability-Lookup

CVE-2026-72686 (GCVE-0-2026-72686)

Vulnerability from cvelistv5 – Published: 2026-08-13 19:10 – Updated: 2026-08-13 20:34

Title

Uncontrolled Recursion in Elasticsearch Leading to Denial of Service

Summary

A flaw in Elasticsearch allows a low-privileged authenticated user to submit a single request containing a crafted user-supplied input. A specific internal component validates the input using a recursive routine and applies no bound to the length of the value being validated, so the validation causes the thread to exhaust its stack. The resulting fatal error is not handled by the surrounding execution paths and terminates the affected node process, producing a denial of service.

Severity

6.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-13 20:23 UTC

CWE

CWE-674 - Uncontrolled Recursion

Assigner

elastic

References

1 reference

URL	Tags
https://discuss.elastic.co/t/elasticsearch-8-19-2…

Impacted products

1 product

Vendor	Product	Version
Elastic	Elasticsearch	Affected: 8.0.0 , ≤ 8.19.19 (semver) Affected: 9.0.0 , ≤ 9.4.4 (semver) Affected: 9.5.0 (semver)

Show details on NVD website

JSON

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FKIE_CVE-2026-72686

Vulnerability from fkie_nvd - Published: 2026-08-13 20:17 - Updated: 2026-08-13 21:18

Severity

6.5 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Summary

References

	URL	Tags
	security@elastic.co	https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-78/389505

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Elasticsearch",
          "vendor": "Elastic",
          "versions": [
            {
              "lessThanOrEqual": "8.19.19",
              "status": "affected",
              "version": "8.0.0",
              "versionType": "semver"
            },
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              "lessThanOrEqual": "9.4.4",
              "status": "affected",
              "version": "9.0.0",
              "versionType": "semver"
            },
            {
              "status": "affected",
              "version": "9.5.0",
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    }
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GHSA-QJ5V-CQ2V-QVGJ

Vulnerability from github – Published: 2026-08-13 21:36 – Updated: 2026-08-13 21:36

Details

Severity

6.5 (Medium)


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

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-72686"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-674"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-08-13T20:17:29Z",
    "severity": "MODERATE"
  },
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  "id": "GHSA-qj5v-cq2v-qvgj",
  "modified": "2026-08-13T21:36:11Z",
  "published": "2026-08-13T21:36:11Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-72686"
    },
    {
      "type": "WEB",
      "url": "https://discuss.elastic.co/t/elasticsearch-8-19-20-9-4-5-9-5-1-security-update-esa-2026-78/389505"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "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-2026-72686 (GCVE-0-2026-72686)

FKIE_CVE-2026-72686

GHSA-QJ5V-CQ2V-QVGJ

Tags

Sightings

Nomenclature