Heap-based buffer overflow in the cpSeparateBufToContigBuf function in tiffcp.c in LibTIFF 4.0.9 allows remote attackers to cause a denial of service (crash) or possibly have unspecified other impact via a crafted TIFF file. Upstream issue: http://bugzilla.maptools.org/show_bug.cgi?id=2798
Created libtiff tracking bugs for this issue: Affects: fedora-all [bug 1595576] Created mingw-libtiff tracking bugs for this issue: Affects: epel-7 [bug 1595578] Affects: fedora-all [bug 1595577]
Raised CVSSv3 to 5.3/CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L because I do not exclude something more than a simple crash is possible with this flaw. Indeed you can overwrite many bytes after the limits of an heap-allocated buffer, thus code execution through heap manipulation is not excluded.
The flaw is in the tiffcp binary and not in the libtiff library, thus programs that use libtiff are not affected.
Patch is not available upstream yet.
This issue has been addressed in the following products: Red Hat Enterprise Linux 7 Via RHSA-2019:2053 https://access.redhat.com/errata/RHSA-2019:2053
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-2018-12900
This issue has been addressed in the following products: Red Hat Enterprise Linux 8 Via RHSA-2019:3419 https://access.redhat.com/errata/RHSA-2019:3419