Bug 849368 (CVE-2012-3505)

Summary: CVE-2012-3505 tinyproxy: multiple headers hashmap DoS
Product: [Other] Security Response Reporter: Kurt Seifried <kseifried>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: NEW --- QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: gabriel, jeremy, madam
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard: impact=low,public=20120814,reported=20120817,source=oss-security,cvss2=5.0/AV:N/AC:L/Au:N/C:N/I:N/A:P,fedora-all/tinyproxy=affected,epel-all/tinyproxy=affected
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: ---
Bug Depends On: 849370, 849369    
Bug Blocks:    
Description Flags
CVE-2012-3505-tinyproxy-randomized-hashmaps.patch none

Description Kurt Seifried 2012-08-18 17:54:05 EDT
gpernot reports:

Bug 110 - algorithmic complexity denial of service 

randomized hashmaps to prevent DOS attacks

hashmap are not randomized, so that it is possible to forge fake headers that 
will always go into the same bucket. 
try 'curl' via tinyproxy and without it to 
convince you (~8 MB of headers). I'll remove this url as soon as bug is 

attached patch should solve this. it's certainly perfectible, though 
(autoconf for time() and rand() are missing...).

even with this patch, it takes ages. maybe headers should be sanitized before 
hiting the buckets...

Created attachment 60 [details]
limit number of headers to prevent DoS attacks

External references:
Comment 1 Kurt Seifried 2012-08-18 17:55:06 EDT
Created tinyproxy tracking bugs for this issue

Affects: fedora-all [bug 849369]
Comment 2 Kurt Seifried 2012-08-18 17:56:32 EDT
Created tinyproxy tracking bugs for this issue

Affects: epel-all [bug 849370]
Comment 3 Kurt Seifried 2012-08-18 17:56:51 EDT
Created attachment 605402 [details]
Comment 4 Kurt Seifried 2012-08-18 17:57:11 EDT
Created attachment 605403 [details]
Comment 5 Michael Adam 2014-12-12 20:10:29 EST
Believe it or not:
Fixes pushed to upstream and will be released soon with Tinyproxy 1.8.4.
Comment 6 Michael Adam 2016-01-01 19:09:15 EST
Upstream release including fix available at


(Note: upstream hosting is currently changing.)