Description
The unformat_24bit_color function in the format parsing code in Irssi before 0.8.20, when compiled with true-color enabled, allows remote attackers to cause a denial of service (heap corruption and crash) via an incomplete 24bit color code.
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 | irssi | 0.8.20-1 | — |
| Debian 13 | irssi | 0.8.20-1 | — |
| Debian 12 | irssi | 0.8.20-1 | — |
| Debian 8 | irssi | 0.8.17-1+deb8u1 | DSA-3672-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | irssi | 0.8.19-1ubuntu1.2 | USN-3086-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SUSE Package Hub 12 | irssi | 0.8.20-9.1 | openSUSE-SU-2016:2524-1, SUSE-SU-2016:2524-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | irssi | 0.8.20-3.1 | openSUSE-SU-2024:10455-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.3 | irssi | 0.8.20-r0 | — |
| Alpine v3.2 | irssi | 0.8.20-r0 | — |
Advisories 5
- USN-3086-1 irssi vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DSA-3672-1 irssi - security update Debian Security (DSA / DLA) · Mar 9, 2026
- openSUSE-SU-2024:10455-1 irssi-0.8.20-3.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:2524-1 Security update for irssi SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2016:2524-1 Security update for irssi SUSE / openSUSE Security Updates · Feb 4, 2026
References
- DSA-3672 vendor-advisory
- https://irssi.org/security/irssi_sa_2016.txt
- 1036868 vdb-entry
- USN-3086-1 vendor-advisory