Bug 1899520 (CVE-2020-25725)

Summary: CVE-2020-25725 xpdf: sending crafted a PDF document to the pdftops tool could result in DoS
Product: [Other] Security Response Reporter: Michael Kaplan <mkaplan>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED UPSTREAM QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: pertusus, spotrh
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: ---
Doc Text:
In Xpdf 4.02, SplashOutputDev::endType3Char(GfxState *state) SplashOutputDev.cc:3079 is trying to use the freed `t3GlyphStack->cache`, which causes an `heap-use-after-free` problem. The codes of a previous fix for nested Type 3 characters wasn't correctly handling the case where a Type 3 char referred to another char in the same Type 3 font.
Story Points: ---
Clone Of: Environment:
Last Closed: 2020-11-19 17:28:49 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: 1899521, 1899522, 1899523    
Bug Blocks:    

Description Michael Kaplan 2020-11-19 13:28:55 UTC
In Xpdf 4.02, SplashOutputDev::endType3Char(GfxState *state) SplashOutputDev.cc:3079 is trying to use the freed `t3GlyphStack->cache`, which causes an `heap-use-after-free` problem. The codes of a previous fix for nested Type 3 characters wasn't correctly handling the case where a Type 3 char referred to another char in the same Type 3 font.

Comment 1 Michael Kaplan 2020-11-19 13:28:58 UTC
Acknowledgments:

Name: Mike Zhang (Pangu Lab)

Comment 2 Michael Kaplan 2020-11-19 13:29:00 UTC
External References:

https://forum.xpdfreader.com/viewtopic.php?f=3&t=41915

Comment 3 Michael Kaplan 2020-11-19 13:30:47 UTC
Created xpdf tracking bugs for this issue:

Affects: epel-6 [bug 1899523]
Affects: epel-7 [bug 1899522]
Affects: fedora-all [bug 1899521]

Comment 4 Product Security DevOps Team 2020-11-19 17:28:49 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.