CVE-2026-1979
Publication date 6 February 2026
Last updated 11 September 2026
Ubuntu priority
Description
A flaw has been found in mruby up to 3.4.0. This affects the function mrb_vm_exec of the file src/vm.c of the component JMPNOT-to-JMPIF Optimization. Executing a manipulation can lead to use after free. The attack needs to be launched locally. The exploit has been published and may be used. This patch is called e50f15c1c6e131fa7934355eb02b8173b13df415. It is advisable to implement a patch to correct this issue.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| mruby | 26.04 LTS resolute |
Needs evaluation
|
| 24.04 LTS noble |
Needs evaluation
|
|
| 22.04 LTS jammy |
Needs evaluation
|
|
| 20.04 LTS focal |
Needs evaluation
|
|
| 18.04 LTS bionic |
Needs evaluation
|
|
| 16.04 LTS xenial |
Needs evaluation
|
Severity score breakdown
CVSS version:
Base score
1.9 · Low
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
Base score
5.3 · Medium
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
References
Other references
- https://www.cve.org/CVERecord?id=CVE-2026-1979
- https://github.com/mruby/mruby/issues/6701
- https://github.com/sysfce2/mruby/commit/e50f15c1c6e131fa7934355eb02b8173b13df415
- https://github.com/mruby/mruby/
- https://github.com/mruby/mruby/issues/6701#issue-3802609843
- https://vuldb.com/?ctiid.344501
- https://vuldb.com/?id.344501
- https://vuldb.com/?submit.743377