CVE-2026-1979

Severity CVSS v4.0:

MEDIUM

Type:

CWE-119 Buffer Errors

Publication date:

06/02/2026

Last modified:

06/02/2026

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.

Impact

Vector 4.0

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 CVSS v4.0 Severity and Metrics:

Base Score: 4.80 MEDIUM
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

Attack Vector (AV): Local
Attack Complexity (AC): Low
Attack Requirements (AT): None
Privileges Required (PR): Low
User Interaction (UI): None
Confidentiality (VC): Low
Integrity (VI): Low
Availability (VA): Low
Confidentiality (SC): None
Integrity (SI): None
Availability (SA): None
Exploit Maturity (E): POC

Base Score 4.0

4.80

Severity 4.0

MEDIUM

Vector 3.x

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L CVSS v3.1 Severity and Metrics:

Base Score: 5.30 MEDIUM
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L

Attack Vector (AV): Local
Attack Complexity (AC): Low
Privileges Required (PR): Low
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): Low
Integrity (I): Low
Availability (A): Low

Base Score 3.x

5.30

Severity 3.x

MEDIUM

Vector 2.0

AV:L/AC:L/Au:S/C:P/I:P/A:P CVSS v2.0 Severity and Metrics:

Base Score: 4.30 MEDIUM
Vector: AV:L/AC:L/Au:S/C:P/I:P/A:P

Attack Vector (AV): Local
Attack Complexity (AC): Low
Authentication (Au): Single
Confidentiality (C): Physical
Integrity (I): Physical
Availability (A): Physical

Base Score 2.0

4.30

Severity 2.0

MEDIUM

CVE-2026-1979

Description

Impact

References to Advisories, Solutions, and Tools