Bug 1531397 (CVE-2017-1000422)

Summary: CVE-2017-1000422 gdk-pixbuf: Integer overflow in io-gif.c:gif_get_lzw() can lead to memory corruption and potential code execution
Product: [Other] Security Response Reporter: Sam Fowler <sfowler>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: bruno, extras-orphan, kevin, mclasen, otte
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2018-01-22 04:45:03 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:    
Bug Blocks: 1531399    

Description Sam Fowler 2018-01-05 05:31:58 UTC 
Gnome gdk-pixbuf 2.36.8 and older is vulnerable to several integer overflows in the io-gif.c:gif_get_lzw() function resulting in memory corruption and potential code execution.


References:
https://bugzilla.gnome.org/show_bug.cgi?id=785973
https://git.gnome.org/browse/gdk-pixbuf/commit/?id=0012e06
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2017-1000422
https://bugzilla.novell.com/show_bug.cgi?id=1074462
Comment 1 Huzaifa S. Sidhpurwala 2018-01-22 04:45:03 UTC 
Analysis:

When rendering very large GIF files, gdk-pixbuf2 would previously fail after attempting to allocate memory because of a possible integer overflow, since frame_len * frame_height would be result in an overflow.

https://git.gnome.org/browse/gdk-pixbuf/commit/?id=0012e06 (patch fixing this CVE) detects the overflow before attempting to allocate memory.

Therefore essentially the flaw is already mitigated in the existing code. It is preferable to be able to detect an overflow before attempting memory, but not doing so should not be a flaw in itself.