Description
Integer signedness error in ansi.c for GNU screen 4.0.1 and earlier, and 3.9.15 and earlier, allows local users to execute arbitrary code via a large number of ";" (semicolon) characters in escape sequences, which leads to a buffer overflow.
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 | screen | 4.0.2-0.1 | — |
| Debian 13 | screen | 4.0.2-0.1 | — |
| Debian 12 | screen | 4.0.2-0.1 | — |
| Debian 3.0 | screen | 3.9.11-5woody1 | DSA-408 |
Advisories 1
- DSA-408 screen - integer overflow Debian Security (DSA / DLA) · Mar 9, 2026
References
- 10539 third-party-advisory
- 20031127 GNU screen buffer overflow mailing-list
- DSA-408 vendor-advisory
- CLA-2004:809 vendor-advisory
- MDKSA-2003:113 vendor-advisory
- http://groups.yahoo.com/group/gnu-screen/message/3118