Bug 1038530

Summary: php-htmlpurifier-htmlpurifier: hash length extension in HTMLPurifier
Product: [Other] Security Response Reporter: Ratul Gupta <ratulg>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED UPSTREAM QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: david
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: php-htmlpurifier-htmlpurifier 4.6.0 Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2019-06-08 02:31:06 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On: 1038532    
Bug Blocks:    

Description Ratul Gupta 2013-12-05 09:46:23 UTC 
HTMLPurifier, a standards-compliant HTML filter library written in PHP, was found to have a vulnerability, which allows the attacker to carry out a "Hash Length Extension" attack.

Class HTMLPurifier_URIFilter_Munge implements a URI filter that replaces all links with a formatted URL. To prevent links from being altered HTMLPurifier allows specifying a secret key via "URI.MungeSecretKey" configuration directive. However, this signature generation method is susceptible to a hash length extension attack.

This vulnerability allows attackers to append an arbitrary value to the signed data without knowing the secret key. This may cause other vulnerabilities in the web applications, which use signature generated by HTMLPurifier to keep the links from being altered.

References:
http://seclists.org/bugtraq/2013/Dec/16
http://www.securityfocus.com/archive/1/530142
http://en.securitylab.ru/lab/PT-2013-63
Comment 1 Ratul Gupta 2013-12-05 09:47:26 UTC 
Created php-htmlpurifier-htmlpurifier tracking bugs for this issue:

Affects: fedora-all [bug 1038532]
Comment 3 Fedora Update System 2014-08-23 01:56:31 UTC 
php-htmlpurifier-htmlpurifier-4.6.0-1.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 4 Fedora Update System 2014-08-23 01:58:28 UTC 
php-htmlpurifier-htmlpurifier-4.6.0-1.fc19 has been pushed to the Fedora 19 stable repository.  If problems still persist, please make note of it in this bug report.
Comment 5 Product Security DevOps Team 2019-06-08 02:31:06 UTC 
This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.