ELA-751-1 giflib security update

multiple file format vulnerabilities

Version4.1.6-11+deb8u2 (jessie), 5.1.4-0.4+deb9u1 (stretch)
Related CVEs CVE-2016-3977 CVE-2018-11490 CVE-2019-15133

This update fixes two file format vulnerabilities in giflib and one in the gif2rgb utility.


Heap-based buffer overflow in util/gif2rgb.c in gif2rgb allows
remote attackers to cause a denial of service (application crash)
via the background color index in a GIF file


The DGifDecompressLine function in dgif_lib.c, as later shipped in
cgif.c in sam2p 0.49.4, has a heap-based buffer overflow because a
certain "Private->RunningCode - 2" array index is not checked.  This
will lead to a denial of service or possibly unspecified other


A malformed GIF file triggers a divide-by-zero exception in the
decoder function DGifSlurp in dgif_lib.c if the height field of the
ImageSize data structure is equal to zero.

For Debian 8 jessie, these problems have been fixed in version 4.1.6-11+deb8u2.

For Debian 9 stretch, these problems have been fixed in version 5.1.4-0.4+deb9u1.

We recommend that you upgrade your giflib packages.

Further information about Extended LTS security advisories can be found in the dedicated section of our website.