CVE-2025-37731Network attack vectorHinoki check available

User impersonation via ambiguous Subject-DN extraction

Published Dec 15, 2025 · Updated Dec 15, 2025

Improper authentication in Elastic Elasticsearch's PKI realm allows remote authenticated users to impersonate other users with a client certificate. PkiRealm passes the rendered Subject DN to the username_pattern regex, allowing crafted RDN text to make the pattern extract an unintended account principal. Exposure requires an enabled PKI realm and a specially crafted client certificate signed by a trusted CA; successful access carries the impersonated user's mapped roles.

CVSS severity6.8
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Improper authentication in Elastic Elasticsearch's PKI realm allows remote authenticated users to impersonate other users with a client certificate. PkiRealm passes the rendered Subject DN to the username_pattern regex, allowing crafted RDN text to make the pattern extract an unintended account principal. Exposure requires an enabled PKI realm and a specially crafted client certificate signed by a trusted CA; successful access carries the impersonated user's mapped roles.

The record

CVE
CVE-2025-37731
Published
Dec 15, 2025
Updated
Dec 15, 2025
Vendor
Elastic
Product
Elasticsearch
Classifications
CWE-287, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 15, 2025CVE publishedPublication date reported by the CVE source.
  2. Dec 15, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.0.0 <=7.17.29
  2. Affected versionversion=8.0.0 <=8.19.7
  3. Affected versionversion=9.0.0 <=9.1.7
  4. Affected versionversion=9.2.0 <=9.2.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Elastic · Elasticsearchversion=7.0.0 <=7.17.29; version=8.0.0 <=8.19.7; version=9.0.0 <=9.1.7; version=9.2.0 <=9.2.1

Published CVSS scores

6.8ElasticCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N
7.4NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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