Description
The CHECK macro in mrbgems/mruby-sprintf/src/sprintf.c in mruby 1.4.1 contains a signed integer overflow, possibly leading to out-of-bounds memory access because the mrb_str_resize function in string.c does not check for a negative length.
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 | mruby | 2.0.0-1 | — |
| Debian 13 | mruby | 2.0.0-1 | — |
| Debian 12 | mruby | 2.0.0-1 | — |
| Debian 9 | mruby | 1.2.0+20161228+git30d5424a-1+deb9u1 | DLA-2996-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | mruby | No fix yet | — |
| Ubuntu 16.04 LTS | mruby | No fix yet | — |
Advisories 1
- DLA-2996-1 mruby - security update Debian Security (DSA / DLA) · Mar 9, 2026