A gif2apng security update has been released for Debian GNU/Linux 9 LTS to address three issues.

DLA 2937-1: gif2apng security update

- -------------------------------------------------------------------------
Debian LTS Advisory DLA-2937-1 debian-lts@lists.debian.org
  https://www.debian.org/lts/security/ Anton Gladky
March 07, 2022   https://wiki.debian.org/LTS
- -------------------------------------------------------------------------

Package : gif2apng
Version : 1.9+srconly-2+deb9u2
CVE ID : CVE-2021-45909 CVE-2021-45910 CVE-2021-45911

Three issues have been discovered in gif2apng: tool for converting animated GIF images to APNG format.

CVE-2021-45909:

heap-based buffer overflow vulnerability in the DecodeLZW function.
It allows an attacker to write a large amount of arbitrary data outside the
boundaries of a buffer.

CVE-2021-45910:

heap-based buffer overflow within the main function. It allows an attacker
to write data outside of the allocated buffer.

CVE-2021-45911:

heap based buffer overflow in processing of delays in the main function.

For Debian 9 stretch, these problems have been fixed in version
1.9+srconly-2+deb9u2.

We recommend that you upgrade your gif2apng packages.

For the detailed security status of gif2apng please refer to
its security tracker page at:
  https://security-tracker.debian.org/tracker/gif2apng

Further information about Debian LTS security advisories, how to apply
these updates to your system and frequently asked questions can be
found at:   https://wiki.debian.org/LTS