Bug 1388386 (CVE-2016-8622)

Summary: CVE-2016-8622 curl: URL unescape heap overflow via integer truncation
Product: [Other] Security Response Reporter: Andrej Nemec <anemec>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: bmcclain, bodavis, cfergeau, csutherl, dbhole, dblechte, eedri, erik-fedora, gzaronik, hhorak, jclere, jorton, kanderso, kdudka, lgao, lsurette, luhliari, mbabacek, mgoldboi, michal.skrivanek, mike, mturk, myarboro, omajid, paul, rh-spice-bugs, rwagner, security-response-team, sherold, slawomir, srevivo, twalsh, weli, ykaul
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: curl 7.51.0 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2019-06-08 03:01:03 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1390894, 1390895, 1390896    
Bug Blocks: 1388393    
Attachments:
Description Flags
Upstream patch none

Description Andrej Nemec 2016-10-25 08:32:56 UTC 
The URL percent-encoding decode function in libcurl is called
`curl_easy_unescape`. Internally, even if this function would be made to
allocate a unscape destination buffer larger than 2GB, it would return that
new length in a signed 32 bit integer variable, thus the length would get
either just truncated or both truncated and turned negative. That could then
lead to libcurl writing outside of its heap based buffer.

This can be triggered by a user on a 64bit system if the user can send in a
custom (very large) URL to a libcurl using program.

External References:

https://curl.haxx.se/docs/adv_20161102H.html
Comment 1 Andrej Nemec 2016-10-25 09:02:01 UTC 
Created attachment 1213778 [details]
Upstream patch
Comment 2 Adam Mariš 2016-11-02 08:28:46 UTC 
Created curl tracking bugs for this issue:

Affects: fedora-all [bug 1390894]
Comment 3 Adam Mariš 2016-11-02 08:29:00 UTC 
Created mingw-curl tracking bugs for this issue:

Affects: fedora-all [bug 1390895]
Affects: epel-7 [bug 1390896]
Comment 6 errata-xmlrpc 2018-08-16 16:07:41 UTC 
This issue has been addressed in the following products:

  Red Hat JBoss Core Services

Via RHSA-2018:2486 https://access.redhat.com/errata/RHSA-2018:2486
Comment 7 errata-xmlrpc 2018-11-13 08:33:39 UTC 
This issue has been addressed in the following products:

  Red Hat Software Collections for Red Hat Enterprise Linux 6
  Red Hat Software Collections for Red Hat Enterprise Linux 7
  Red Hat Software Collections for Red Hat Enterprise Linux 7.4 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.5 EUS
  Red Hat Software Collections for Red Hat Enterprise Linux 7.6 EUS

Via RHSA-2018:3558 https://access.redhat.com/errata/RHSA-2018:3558