Description
A vulnerability, which was classified as problematic, was found in mruby up to 3.4.0-rc2. Affected is the function scope_new of the file mrbgems/mruby-compiler/core/codegen.c of the component nregs Handler. The manipulation leads to heap-based buffer overflow. An attack has to be approached locally. The exploit has been disclosed to the public and may be used. The name of the patch is 1fdd96104180cc0fb5d3cb086b05ab6458911bb9. It is recommended to apply a patch to fix this issue.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| — | mruby | 3.4.0-rc1, 3.4.0-rc2 | — |
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 | 3.4.0-2 | — |
| Debian 13 | mruby | No fix yet | — |
| Debian 12 | mruby | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | mruby | No fix yet | — |
| Ubuntu 26.04 LTS | mruby | No fix yet | — |
| Ubuntu 25.10 | mruby | No fix yet | — |
| Ubuntu 24.04 LTS | mruby | No fix yet | — |
| Ubuntu 22.04 LTS | mruby | No fix yet | — |
Show 3 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 20.04 LTS | mruby | No fix yet | — |
| Ubuntu 18.04 LTS | mruby | No fix yet | — |
| Ubuntu 16.04 LTS | mruby | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | mruby | 3.4.0-1.1 | openSUSE-SU-2025:15333-1 |
Advisories 1
- openSUSE-SU-2025:15333-1 libmruby3_4_0-3.4.0-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
References
- VDB-315156 | mruby nregs codegen.c scope_new heap-based overflow vdb-entry technical-description
- VDB-315156 | CTI Indicators (IOB, IOC, IOA) signature permissions-required
- Submit #607683 | mruby mruby 3.4.0-rc2 (commit dd68681) Heap-based Buffer Overflow third-party-advisory
- https://github.com/mruby/mruby/issues/6509 issue-tracking
- https://github.com/mruby/mruby/issues/6509#event-17145516649 issue-tracking
- https://github.com/user-attachments/files/19619499/mruby_crash.txt exploit
- https://github.com/mruby/mruby/commit/1fdd96104180cc0fb5d3cb086b05ab6458911bb9 patch