Apache HTTP Server 2.2.24/2.2.32 HTTP Strict Parsing ap_find_token Request Header input validation

CVSS Meta Temp Score
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CTI Interest Score
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8.4$0-$5k0.00

A vulnerability was found in Apache HTTP Server 2.2.24/2.2.32 (Web Server). It has been declared as critical. Affected by this vulnerability is the function ap_find_token of the component HTTP Strict Parsing. The manipulation as part of a Request Header leads to a input validation vulnerability. The CWE definition for the vulnerability is CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The HTTP strict parsing changes added in Apache httpd 2.2.32 and 2.4.24 introduced a bug in token list parsing, which allows ap_find_token() to search past the end of its input string. By maliciously crafting a sequence of request headers, an attacker may be able to cause a segmentation fault, or to force ap_find_token() to return an incorrect value.

The bug was discovered 06/19/2017. The weakness was disclosed 06/20/2017 (Website). The advisory is shared at lists.apache.org. This vulnerability is known as CVE-2017-7668 since 04/11/2017. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 100995 (Apache 2.2.x < 2.2.33-dev / 2.4.x < 2.4.26 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Web Servers and running in the context r. The commercial vulnerability scanner Qualys is able to test this issue with plugin 196833 (Ubuntu Security Notification for Apache2 Vulnerabilities (USN-3340-1)).

Upgrading to version 2.4.26 eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (100995). The entries 21337, 63776, 90671 and 96545 are pretty similar.

Productinfo

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Support

  • end of life (old version)

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 8.5
VulDB Meta Temp Score: 8.4

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
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Exploitinginfo

Class: Input validation
CWE: CWE-20
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 100995
Nessus Name: Apache 2.2.x < 2.2.33-dev / 2.4.x < 2.4.26 Multiple Vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 703896
OpenVAS Name: Debian Security Advisory DSA 3896-1 (apache2 - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: HTTP Server 2.4.26

Timelineinfo

04/11/2017 🔍
06/19/2017 +69 days 🔍
06/19/2017 +0 days 🔍
06/19/2017 +0 days 🔍
06/19/2017 +0 days 🔍
06/20/2017 +1 days 🔍
06/20/2017 +0 days 🔍
06/22/2017 +2 days 🔍
12/08/2022 +1995 days 🔍

Sourcesinfo

Vendor: apache.org

Advisory: RHSA-2017:2479
Researcher: Javier Jim, amp, eacute, nez
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-7668 (🔍)
OVAL: 🔍

SecurityTracker: 1038711
SecurityFocus: 99137 - Apache HTTP Server CVE-2017-7668 Denial of Service Vulnerability

See also: 🔍

Entryinfo

Created: 06/20/2017 11:51
Updated: 12/08/2022 16:44
Changes: 06/20/2017 11:51 (78), 10/19/2019 10:24 (5), 12/29/2020 10:39 (3), 12/29/2020 10:43 (1), 12/08/2022 16:44 (3)
Complete: 🔍

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