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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | libsixel | 1.8.6-1 | — |
| Debian 13 | libsixel | 1.8.6-1 | — |
| Debian 12 | libsixel | 1.8.6-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | libsixel | No fix yet | — |
| Ubuntu 26.04 LTS | libsixel | No fix yet | — |
| Ubuntu 25.10 | libsixel | No fix yet | — |
| Ubuntu 24.04 LTS | libsixel | No fix yet | — |
| Ubuntu 22.04 LTS | libsixel | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | libsixel | No fix yet | — |
| Ubuntu 18.04 LTS | libsixel | No fix yet | — |
| Ubuntu 16.04 LTS | libsixel | No fix yet | — |