CVE-2011-4858

Apache Tomcat < 5.5.35, 6.x < 6.0.35, 7.x < 7.0.23 - Denial of Service via Hash Collision in Form Parameters

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 2 public exploits for CVE-2011-4858. PoCs published by Alexander Klink, Julian Waelde, Scott A. Crosby, Dan S. Wallach, Krzysztof Kotowicz, Christian Mehlmauer, including Metasploit module auxiliary/dos/http/hashcollision_dos.

AI-analyzed exploit summary This Metasploit module exploits a denial-of-service (DoS) vulnerability in PHP and Java web servers by generating a large number of colliding hash values in POST parameters, causing excessive CPU consumption. It includes payload generation for both PHP and Java hash functions and sends multiple HTTP requests to the target.

Description

Apache Tomcat before 5.5.35, 6.x before 6.0.35, and 7.x before 7.0.23 computes hash values for form parameters without restricting the ability to trigger hash collisions predictably, which allows remote attackers to cause a denial of service (CPU consumption) by sending many crafted parameters.

Exploits (2)

metasploit WORKING POC
by Alexander Klink, Julian Waelde, Scott A. Crosby, Dan S. Wallach, Krzysztof Kotowicz, Christian Mehlmauer · rubypoc
https://github.com/rapid7/metasploit-framework/blob/master/modules/auxiliary/dos/http/hashcollision_dos.rb

This Metasploit module exploits a denial-of-service (DoS) vulnerability in PHP and Java web servers by generating a large number of colliding hash values in POST parameters, causing excessive CPU consumption. It includes payload generation for both PHP and Java hash functions and sends multiple HTTP requests to the target.

Classification
Working Poc 100%
Attack Type
Dos
Complexity
Moderate
Reliability
Reliable
Target: PHP and Java web servers (e.g., Apache with PHP, Tomcat, Glassfish, Geronimo)
No auth needed
Prerequisites: Network access to the target web server
devstral-2 · analyzed Jun 05, 2026 Full analysis →
exploitdb WORKING POC
phpwebappsphp
https://www.exploit-db.com/exploits/2012

This exploit demonstrates a SQL injection vulnerability in MyBulletinBoard (MyBB) <= 1.1.5 via the 'CLIENT-IP' HTTP header. It retrieves the admin's login key through blind SQL injection and creates a new admin user by leveraging the stolen session.

Classification
Working Poc 95%
Attack Type
Sqli
Complexity
Moderate
Reliability
Reliable
Target: MyBulletinBoard (MyBB) <= 1.1.5
No auth needed
Prerequisites: Target must be running MyBB <= 1.1.5 · Network access to the target
devstral-2 · analyzed Feb 19, 2026 Full analysis →

References (26)

Core 26
Core References
Various Sources x_refsource_misc
http://www.nruns.com/_downloads/advisory28122011.pdf
Various Sources x_refsource_misc
http://www.ocert.org/advisories/ocert-2011-003.html
Third Party Advisory vendor-advisory x_refsource_debian
http://www.debian.org/security/2012/dsa-2401
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0325.html
Mailing List vendor-advisory x_refsource_hp
http://marc.info/?l=bugtraq&m=136485229118404&w=2
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0078.html
Third Party Advisory, VDB Entry vdb-entry x_refsource_bid
http://www.securityfocus.com/bid/51200
Issue Tracking x_refsource_confirm
https://bugzilla.redhat.com/show_bug.cgi?id=750521
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/48791
Third Party Advisory, VDB Entry vdb-entry signature x_refsource_oval
https://oval.cisecurity.org/repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A18886
Various Sources x_refsource_confirm
http://tomcat.apache.org/tomcat-7.0-doc/changelog.html
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0075.html
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0074.html
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/48549
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0089.html
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/54971
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/48790
Third Party Advisory third-party-advisory x_refsource_secunia
http://secunia.com/advisories/55115
US Government Resource third-party-advisory x_refsource_cert-vn
http://www.kb.cert.org/vuls/id/903934
Mailing List vendor-advisory x_refsource_hp
http://marc.info/?l=bugtraq&m=133294394108746&w=2
Mailing List vendor-advisory x_refsource_hp
http://marc.info/?l=bugtraq&m=132871655717248&w=2
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0406.html
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0076.html
Vendor Advisory vendor-advisory x_refsource_redhat
http://rhn.redhat.com/errata/RHSA-2012-0077.html

Scores

EPSS 0.7660
EPSS Percentile 99.0%

Details

CWE
CWE-399
Status published
Products (50)
apache/tomcat 5.5.35
apache/tomcat 6.0.0
apache/tomcat 6.0.1
apache/tomcat 6.0.2
apache/tomcat 6.0.3
apache/tomcat 6.0.4
apache/tomcat 6.0.5
apache/tomcat 6.0.6
apache/tomcat 6.0.7
apache/tomcat 6.0.8
... and 40 more
Published Jan 05, 2012
Tracked Since Feb 18, 2026