It was noticed that in Pillow before 7.1.0, there are multiple out-of-bounds reads in libImaging/FliDecode.c.

For Debian 9 stretch, this problem has been fixed in version 4.0.0-4+deb9u2.

We recommend that you upgrade your pillow packages.

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

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