| Name | CVE-2020-21677 |
| Description | A heap-based buffer overflow in the sixel_encoder_output_without_macro function in encoder.c of Libsixel 1.8.4 allows attackers to cause a denial of service (DOS) via converting a crafted PNG file into Sixel format. |
| Source | CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
Vulnerable and fixed packages
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|
| libsixel (PTS) | jessie | 1.1.2-1 | vulnerable |
| stretch | 1.5.2-2+deb9u1 | vulnerable |
| buster | 1.8.2-1+deb10u1 | vulnerable |
| bullseye | 1.8.6-2 | fixed |
| sid, trixie, bookworm | 1.10.3-3 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|
| libsixel | source | jessie | (unfixed) | end-of-life | | |
| libsixel | source | (unstable) | 1.8.6-1 | | | |
Notes
[buster] - libsixel <no-dsa> (Minor issue)
[stretch] - libsixel <no-dsa> (Minor issue)
https://github.com/saitoha/libsixel/issues/123
https://github.com/saitoha/libsixel/commit/0b1e0b3f7b44233f84e5c9f512f8c90d6bbbe33d