Bug 1340116 (CVE-2016-5044)

Summary: CVE-2016-5044 libdwarf: Heap-based buffer overflow in update_entry()
Product: [Other] Security Response Reporter: Andrej Nemec <anemec>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED WONTFIX QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: fche, orion
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Last Closed: 2016-05-26 13:42:32 UTC Type: ---
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Description Andrej Nemec 2016-05-26 13:23:02 UTC
A vulnerability was found in libdwarf in dwarf_elf_access.c:1071. A crafted ELF file may lead to a large offset value, which bigger than the size of target_section heap chunk, then this WRITE_UNALIGNED() function will write the value of &outval out of the heap chunk. offset is a 64bit unsigned int value, so this is more than a heap overflow bug, but also a Out-of-Bound write bug. So WRITE_UNALIGNED() need more strictly checking to prevent this. 

References:

http://seclists.org/oss-sec/2016/q2/393

External references:

https://www.prevanders.net/dwarfbug.html

Upstream fix:

https://sourceforge.net/p/libdwarf/code/ci/98a3da1e8237fe0d45b67ef77f3fa5ed9ff0215f

Comment 1 Tom Hughes 2016-05-26 13:29:35 UTC
Already fixed in Fedora.