CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.4	$0-$5k	0.00

Summaryinfo

A vulnerability has been found in Apache HTTP Server up to 2.0.50 and classified as problematic. The impacted element is an unknown function in the library apr-util of the component IPv6 Handler. Performing a manipulation results in denial of service. This vulnerability was named CVE-2004-0747. The attack may be initiated remotely. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Apache HTTP Server up to 2.0.50 (Web Server). It has been classified as critical. This affects an unknown part in the library apr-util of the component IPv6 Handler. The manipulation with an unknown input leads to a denial of service vulnerability. CWE is classifying the issue as CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. This is going to have an impact on availability. The summary by CVE is:

Buffer overflow in Apache 2.0.50 and earlier allows local users to gain apache privileges via a .htaccess file that causes the overflow during expansion of environment variables.

The weakness was presented 09/15/2004 by Ulf Harnhammar with NISCC (Website). It is possible to read the advisory at uniras.gov.uk. This vulnerability is uniquely identified as CVE-2004-0747 since 07/26/2004. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 14766 (GLSA-200409-21 : Apache 2, mod_dav: Multiple vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Gentoo Local Security Checks. The commercial vulnerability scanner Qualys is able to test this issue with plugin 86678 (Multiple Apache Web Server Vulnerabilities prior to version 2.0.51).

Upgrading eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at httpd.apache.org. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at X-Force (17384), Tenable (14766), SecurityFocus (BID 11182†), OSVDB (9991†) and Secunia (SA12540†). See VDB-844 for similar entry. Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Web Server

Vendor

• Apache

Name

• HTTP Server

Version

• 2.0.0
• 2.0.1
• 2.0.2
• 2.0.3
• 2.0.4
• 2.0.5
• 2.0.6
• 2.0.7
• 2.0.8
• 2.0.9
• 2.0.10
• 2.0.11
• 2.0.12
• 2.0.13
• 2.0.14
• 2.0.15
• 2.0.16
• 2.0.17
• 2.0.18
• 2.0.19
• 2.0.20
• 2.0.21
• 2.0.22
• 2.0.23
• 2.0.24
• 2.0.25
• 2.0.26
• 2.0.27
• 2.0.28
• 2.0.29
• 2.0.30
• 2.0.31
• 2.0.32
• 2.0.33
• 2.0.34
• 2.0.35
• 2.0.36
• 2.0.37
• 2.0.38
• 2.0.39
• 2.0.40
• 2.0.41
• 2.0.42
• 2.0.43
• 2.0.44
• 2.0.45
• 2.0.46
• 2.0.47
• 2.0.48
• 2.0.49
• 2.0.50

License

• open-source

Support

• end of life (old version)

Website

• Vendor: https://www.apache.org/

CPE 2.3info

• 🔍
• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍
• 🔍

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.7
VulDB Meta Temp Score: 7.4

VulDB Base Score: 7.5
VulDB Temp Score: 6.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Denial of service
CWE: CWE-404
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Proof-of-Concept

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Nessus ID: 14766
Nessus Name: GLSA-200409-21 : Apache 2, mod_dav: Multiple vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Port: 🔍

OpenVAS ID: 100172
OpenVAS Name: Apache Web Server Configuration File Environment Variable Local Buffer Overflow Vulnerability
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

ATK: 236

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: httpd.apache.org

Timelineinfo

07/26/2004 🔍
09/15/2004 +51 days 🔍
09/15/2004 +0 days 🔍
09/15/2004 +0 days 🔍
09/15/2004 +0 days 🔍
09/15/2004 +0 days 🔍
09/15/2004 +0 days 🔍
09/16/2004 +0 days 🔍
09/16/2004 +0 days 🔍
09/17/2004 +1 days 🔍
09/21/2004 +4 days 🔍
10/20/2004 +29 days 🔍
07/11/2025 +7569 days 🔍

Sourcesinfo

Vendor: apache.org

Advisory: uniras.gov.uk
Researcher: Ulf Harnhammar
Organization: NISCC
Status: Confirmed

CVE: CVE-2004-0747 (🔍)
GCVE (CVE): GCVE-0-2004-0747
GCVE (VulDB): GCVE-100-843

OVAL: 🔍

CERT: 🔍
X-Force: 17384 - Apache HTTP Server environment variable configuration file buffer overflow, High Risk
SecurityFocus: 11182 - Apache Web Server Configuration File Environment Variable Local Buffer Overflow Vulnerability
Secunia: 12540 - Apache apr-util Library and Environment Variable Expansion Vulnerabilities, Moderately Critical
OSVDB: 9991 - Apache HTTP Server ap_resolve_env Environment Variable Local Overflow
SecurityTracker: 1011303 - Apache ap_resolve_env() Buffer Overflow in Reading Configuration Files May Let Local Users Gain Elevated Privileges
Vulnerability Center: 5434 - Buffer Overflow in Apache 2.0.50 and Earlier Enables Local Privileges via .htaccess File, Medium
Vupen: ADV-2009-1233

See also: 🔍

Entryinfo

Created: 09/16/2004 11:21
Updated: 07/11/2025 20:54
Changes: 09/16/2004 11:21 (103), 04/16/2019 15:10 (1), 03/09/2021 19:17 (3), 12/16/2024 03:59 (15), 01/16/2025 20:14 (21), 07/11/2025 20:54 (2)
Complete: 🔍
Cache ID: 216:AD3:103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion

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