CVE-2023-0284Network attack vector

Server file manipulation via unsanitized LDAP user IDs

Published Jan 24, 2023 · Updated Mar 27, 2025

Improper input validation in Checkmk 2.1.0p19 and earlier allows remote authenticated users to manipulate server files via LDAP user IDs. The LDAP synchronization path accepts user IDs without the character restrictions applied to local IDs and uses them in per-user web-directory paths. Control of an LDAP user's uid attribute is required; crafted IDs can overwrite another user's web files, delete stored 2FA credentials, or lock out accounts without direct impersonation.

CVSS severity6.8
Medium
EPSS probability0.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Checkmk 2.1.0p19 and earlier allows remote authenticated users to manipulate server files via LDAP user IDs. The LDAP synchronization path accepts user IDs without the character restrictions applied to local IDs and uses them in per-user web-directory paths. Control of an LDAP user's uid attribute is required; crafted IDs can overwrite another user's web files, delete stored 2FA credentials, or lock out accounts without direct impersonation.

The record

CVE
CVE-2023-0284
Published
Jan 24, 2023
Updated
Mar 27, 2025
Vendor
Checkmk GmbH
Product
Checkmk
Classifications
CWE-20, T1565.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 24, 2023CVE publishedPublication date reported by the CVE source.
  2. Mar 27, 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=1.6.0 <=1.6.0p30
  2. Affected versionversion=2.0.0 <=2.0.0p32
  3. Affected versionversion=2.1.0 <=2.1.0p19

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Checkmk GmbH · Checkmkversion=1.6.0 <=1.6.0p30; version=2.0.0 <=2.0.0p32; version=2.1.0 <=2.1.0p19

Published CVSS scores

8.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
6.8Checkmk GmbHCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-20Improper Input Validation
T1565.001Stored Data Manipulation

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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