CVE-2026-1979

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.

CVSS v3 5.3 MEDIUM
CVSS v2.0 4.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.4

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

4.3^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:L/Au:S/C:P/I:P/A:P

Exploitability : 3.1 / Impact : 6.4

Access Vector LOCAL

Access Complexity LOW

Authentication SINGLE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://github.com/mruby/mruby/	Product
https://github.com/mruby/mruby/issues/6701	Exploit Issue Tracking
https://github.com/mruby/mruby/issues/6701#issue-3802609843	Exploit Issue Tracking
https://github.com/sysfce2/mruby/commit/e50f15c1c6e131fa7934355eb02b8173b13df415	Patch
https://vuldb.com/?ctiid.344501	Permissions Required VDB Entry
https://vuldb.com/?id.344501	Third Party Advisory VDB Entry
https://vuldb.com/?submit.743377	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

cpe:2.3:a:mruby:mruby:*:*:*:*:*:ruby:*:*

History

No history.

Information

Published : 2026-02-06 05:16

Updated : 2026-02-28 00:33

NVD link : CVE-2026-1979

Mitre link : CVE-2026-1979

CVE.ORG link : CVE-2026-1979

JSON object : View

Products Affected

mruby

mruby

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

CWE-416

Use After Free

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