FKIE_CVE-2026-1979

Vulnerability from fkie_nvd - Published: 2026-02-06 05:16 - Updated: 2026-06-17 10:16
Severity
5.3 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Summary
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.
References
cna@vuldb.comhttps://github.com/mruby/mruby/Product
cna@vuldb.comhttps://github.com/mruby/mruby/issues/6701Exploit, Issue Tracking
cna@vuldb.comhttps://github.com/mruby/mruby/issues/6701#issue-3802609843Exploit, Issue Tracking
cna@vuldb.comhttps://github.com/sysfce2/mruby/commit/e50f15c1c6e131fa7934355eb02b8173b13df415Patch
cna@vuldb.comhttps://vuldb.com/?ctiid.344501Permissions Required, VDB Entry
cna@vuldb.comhttps://vuldb.com/?id.344501Third Party Advisory, VDB Entry
cna@vuldb.comhttps://vuldb.com/?submit.743377Third Party Advisory, VDB Entry
Impacted products
Vendor Product Version
mruby mruby *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "cpes": [
            "cpe:2.3:a:mruby:mruby:*:*:*:*:*:*:*:*"
          ],
          "modules": [
            "JMPNOT-to-JMPIF Optimization"
          ],
          "product": "mruby",
          "vendor": "n/a",
          "versions": [
            {
              "status": "affected",
              "version": "3.0"
            },
            {
              "status": "affected",
              "version": "3.1"
            },
            {
              "status": "affected",
              "version": "3.2"
            },
            {
              "status": "affected",
              "version": "3.3"
            },
            {
              "status": "affected",
              "version": "3.4.0"
            }
          ]
        }
      ],
      "source": "cna@vuldb.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:mruby:mruby:*:*:*:*:*:ruby:*:*",
              "matchCriteriaId": "F9663307-847C-4A95-9485-4AEA84AAB19E",
              "versionEndIncluding": "3.4.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    },
    {
      "lang": "es",
      "value": "Se ha encontrado una vulnerabilidad en mruby hasta la versi\u00f3n 3.4.0. Esto afecta a la funci\u00f3n mrb_vm_exec del archivo src/vm.c del componente Optimizaci\u00f3n JMPNOT-a-JMPIF. La ejecuci\u00f3n de una manipulaci\u00f3n puede conducir a un uso despu\u00e9s de liberar. El ataque debe lanzarse localmente. El exploit ha sido publicado y puede ser utilizado. Este parche se llama e50f15c1c6e131fa7934355eb02b8173b13df415. Es aconsejable implementar un parche para corregir este problema."
    }
  ],
  "id": "CVE-2026-1979",
  "lastModified": "2026-06-17T10:16:49.260",
  "metrics": {
    "cvssMetricV2": [
      {
        "acInsufInfo": false,
        "baseSeverity": "MEDIUM",
        "cvssData": {
          "accessComplexity": "LOW",
          "accessVector": "LOCAL",
          "authentication": "SINGLE",
          "availabilityImpact": "PARTIAL",
          "baseScore": 4.3,
          "confidentialityImpact": "PARTIAL",
          "integrityImpact": "PARTIAL",
          "vectorString": "AV:L/AC:L/Au:S/C:P/I:P/A:P",
          "version": "2.0"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 6.4,
        "obtainAllPrivilege": false,
        "obtainOtherPrivilege": false,
        "obtainUserPrivilege": false,
        "source": "cna@vuldb.com",
        "type": "Secondary",
        "userInteractionRequired": false
      }
    ],
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "LOW",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.4,
        "source": "cna@vuldb.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "LOCAL",
          "availabilityImpact": "HIGH",
          "baseScore": 5.5,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 1.8,
        "impactScore": 3.6,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "LOCAL",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 1.9,
          "baseSeverity": "LOW",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "PROOF_OF_CONCEPT",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "NONE",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "LOW",
          "vulnConfidentialityImpact": "LOW",
          "vulnIntegrityImpact": "LOW",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "cna@vuldb.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-1979",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-02-06T20:26:13.479778Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-02-06T05:16:12.667",
  "references": [
    {
      "source": "cna@vuldb.com",
      "tags": [
        "Product"
      ],
      "url": "https://github.com/mruby/mruby/"
    },
    {
      "source": "cna@vuldb.com",
      "tags": [
        "Exploit",
        "Issue Tracking"
      ],
      "url": "https://github.com/mruby/mruby/issues/6701"
    },
    {
      "source": "cna@vuldb.com",
      "tags": [
        "Exploit",
        "Issue Tracking"
      ],
      "url": "https://github.com/mruby/mruby/issues/6701#issue-3802609843"
    },
    {
      "source": "cna@vuldb.com",
      "tags": [
        "Patch"
      ],
      "url": "https://github.com/sysfce2/mruby/commit/e50f15c1c6e131fa7934355eb02b8173b13df415"
    },
    {
      "source": "cna@vuldb.com",
      "tags": [
        "Permissions Required",
        "VDB Entry"
      ],
      "url": "https://vuldb.com/?ctiid.344501"
    },
    {
      "source": "cna@vuldb.com",
      "tags": [
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "https://vuldb.com/?id.344501"
    },
    {
      "source": "cna@vuldb.com",
      "tags": [
        "Third Party Advisory",
        "VDB Entry"
      ],
      "url": "https://vuldb.com/?submit.743377"
    }
  ],
  "sourceIdentifier": "cna@vuldb.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-119"
        },
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ],
      "source": "cna@vuldb.com",
      "type": "Secondary"
    }
  ]
}



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