A buffer overflow vulnerability in GetNumSameData() in contrib/lips4/gdevlips.c of Artifex Software GhostScript v9.50 allows a remote attacker to cause a denial of service via a crafted PDF file. This is fixed in v9.51. References: https://bugs.ghostscript.com/show_bug.cgi?id=701792 https://git.ghostscript.com/?p=ghostpdl.git;a=commit;h=9f39ed4a92578a020ae10459643e1fe72573d134
Created ghostscript tracking bugs for this issue: Affects: fedora-all [bug 1870251]
Mitigation: Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Flaw Summary: The GetNumSameData() function in /contrib/lips4/gdevlips.c could perform a buffer overflow due to while loop conditions in an improper order: `while (*curPtr == *(curPtr + count) && maxnum > count)` In this case, `maxnum > count` should be checked prior to dereferencing `curPtr + count` conditions to avoid a potential heap buffer overread. The patch does this.
I was not able to reproduce the issue as described upstream with ASAN on RHEL, but do see the source code line in the file. As such, I've marked it as Low.
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2021:1852 https://access.redhat.com/errata/RHSA-2021:1852
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s): https://access.redhat.com/security/cve/cve-2020-17538