Apache HTTP Server up to 2..4.65 mod_userdir access control

Summaryinfo

A vulnerability labeled as critical has been found in Apache HTTP Server up to 2..4.65. The affected element is an unknown function of the component mod_userdir. Such manipulation leads to access control. This vulnerability is traded as CVE-2025-66200. The attack may be launched remotely. There is no exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Apache HTTP Server up to 2..4.65 and classified as critical. Affected by this issue is an unknown part of the component mod_userdir. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality, integrity, and availability. CVE summarizes:

mod_userdir+suexec bypass via AllowOverride FileInfo vulnerability in Apache HTTP Server. Users with access to use the RequestHeader directive in htaccess can cause some CGI scripts to run under an unexpected userid. This issue affects Apache HTTP Server: from 2.4.7 through 2.4.65. Users are recommended to upgrade to version 2.4.66, which fixes the issue.

The advisory is available at lists.apache.org. This vulnerability is handled as CVE-2025-66200. The exploitation is known to be difficult. The attack may be launched remotely. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 02/04/2026). This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 277495 (Linux Distros Unpatched Vulnerability : CVE-2025-66200), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.4.66 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (277495), EUVD (EUVD-2025-201403) and CERT Bund (WID-SEC-2025-2750). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Fedora Linux
• Ubuntu Linux
• IBM HTTP Server
• SUSE Linux
• IBM Rational ClearCase
• Oracle Linux
• HCL Commerce
• SUSE openSUSE
• RESF Rocky Linux
• IBM Business Automation Workflow
• Apache HTTP Server
• Microsoft Azure Linux

Productinfo

Type

• Web Server

Vendor

• Apache

Name

• HTTP Server

Version

• 2..4.0
• 2..4.1
• 2..4.2
• 2..4.3
• 2..4.4
• 2..4.5
• 2..4.6
• 2..4.7
• 2..4.8
• 2..4.9
• 2..4.10
• 2..4.11
• 2..4.12
• 2..4.13
• 2..4.14
• 2..4.15
• 2..4.16
• 2..4.17
• 2..4.18
• 2..4.19
• 2..4.20
• 2..4.21
• 2..4.22
• 2..4.23
• 2..4.24
• 2..4.25
• 2..4.26
• 2..4.27
• 2..4.28
• 2..4.29
• 2..4.30
• 2..4.31
• 2..4.32
• 2..4.33
• 2..4.34
• 2..4.35
• 2..4.36
• 2..4.37
• 2..4.38
• 2..4.39
• 2..4.40
• 2..4.41
• 2..4.42
• 2..4.43
• 2..4.44
• 2..4.45
• 2..4.46
• 2..4.47
• 2..4.48
• 2..4.49
• 2..4.50
• 2..4.51
• 2..4.52
• 2..4.53
• 2..4.54
• 2..4.55
• 2..4.56
• 2..4.57
• 2..4.58
• 2..4.59
• 2..4.60
• 2..4.61
• 2..4.62
• 2..4.63
• 2..4.64
• 2..4.65

License

• open-source

Website

• Vendor: https://www.apache.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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