Vulnerability-Lookup

CVE-2023-6936 (GCVE-0-2023-6936)

Vulnerability from cvelistv5 – Published: 2024-02-20 21:52 – Updated: 2025-03-26 16:28

Title

Heap-buffer over-read with WOLFSSL_CALLBACKS

Summary

In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).

Severity

5.3 (Medium)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-08-27 14:22 UTC

CWE

CWE-126 - Buffer Over-read

Assigner

wolfSSL CNA under the icscert root

CNA scorecard B 80/100 over 51 records in the last 180 days details

References

2 references

URL	Tags
https://github.com/wolfSSL/wolfssl/pull/6949/	patch
https://www.wolfssl.com/docs/security-vulnerabilities/	vendor-advisory

Impacted products

2 products

Vendor	Product	Version	CPE status
wolfSSL	wolfSSL	Affected: 0 , ≤ 5.6.5 (release bundle)	guessed
wolfssl	wolfssl	Affected: 0 , ≤ 5.6.5 (custom) cpe:2.3:a:wolfssl:wolfssl::::::::

Date Public

2023-12-20 00:00

Credits

Lucca Hirschi (Inria, LORIA) Steve Kremer (Inria, LORIA) Max Ammann (Trail of Bits) tlspuffin

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "affected": [
          {
            "cpes": [
              "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*"
            ],
            "defaultStatus": "unknown",
            "product": "wolfssl",
            "vendor": "wolfssl",
            "versions": [
              {
                "lessThanOrEqual": "5.6.5",
                "status": "affected",
                "version": "0",
                "versionType": "custom"
              }
            ]
          }
        ],
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2023-6936",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-08-27T14:22:41.353325Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-126",
                "description": "CWE-126 Buffer Over-read",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-03-26T16:28:30.322Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      },
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T08:42:08.671Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "patch",
              "x_transferred"
            ],
            "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
          },
          {
            "tags": [
              "vendor-advisory",
              "x_transferred"
            ],
            "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
          }
        ],
        "title": "CVE Program Container"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "modules": [
            "TLS"
          ],
          "product": "wolfSSL",
          "repo": "https://github.com/wolfSSL/wolfssl",
          "vendor": "wolfSSL",
          "versions": [
            {
              "lessThanOrEqual": "5.6.5",
              "status": "affected",
              "version": "0",
              "versionType": "release bundle"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "To be vulnerable, wolfSSL callback functionality (which includes handshake and timeout callback functionality) must must be enabled with:\u003cbr\u003e\u003cb\u003e\u003cspan style=\"background-color: transparent;\"\u003eCFLAGS=\"-DWOLFSSL_CALLBACKS\"\u003c/span\u003e\u003c/b\u003e\u003cbr\u003e\u003cbr\u003eThis option is disabled by default. The default configuration of wolfSSL is not vulnerable."
            }
          ],
          "value": "To be vulnerable, wolfSSL callback functionality (which includes handshake and timeout callback functionality) must must be enabled with:\nCFLAGS=\"-DWOLFSSL_CALLBACKS\"\n\nThis option is disabled by default. The default configuration of wolfSSL is not vulnerable."
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "user": "00000000-0000-4000-9000-000000000000",
          "value": "Lucca Hirschi (Inria, LORIA)"
        },
        {
          "lang": "en",
          "type": "finder",
          "user": "00000000-0000-4000-9000-000000000000",
          "value": "Steve Kremer (Inria, LORIA)"
        },
        {
          "lang": "en",
          "type": "finder",
          "user": "00000000-0000-4000-9000-000000000000",
          "value": "Max Ammann (Trail of Bits)"
        },
        {
          "lang": "en",
          "type": "tool",
          "user": "00000000-0000-4000-9000-000000000000",
          "value": "tlspuffin"
        }
      ],
      "datePublic": "2023-12-20T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\u003cbr\u003e"
            }
          ],
          "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\n"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2024-02-20T21:52:02.441Z",
        "orgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
        "shortName": "wolfSSL"
      },
      "references": [
        {
          "tags": [
            "patch"
          ],
          "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
        },
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003e\u003cspan style=\"background-color: transparent;\"\u003eThe fix for this issue is located in the following GitHub Pull Request: \u003c/span\u003e\u003ca target=\"_blank\" rel=\"nofollow\" href=\"https://github.com/wolfSSL/wolfssl/pull/6949/\"\u003ehttps://github.com/wolfSSL/wolfssl/pull/6949/\u003c/a\u003e\u003c/p\u003e"
            }
          ],
          "value": "The fix for this issue is located in the following GitHub Pull Request:  https://github.com/wolfSSL/wolfssl/pull/6949/ https://github.com/wolfSSL/wolfssl/pull/6949/ \n\n"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "title": " Heap-buffer over-read with WOLFSSL_CALLBACKS",
      "workarounds": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cli\u003eDo not build wolfSSL with \u003cb\u003eWOLFSSL_CALLBACKS\u003c/b\u003e defined\u003c/li\u003e"
            }
          ],
          "value": "  *  Do not build wolfSSL with WOLFSSL_CALLBACKS defined\n"
        }
      ],
      "x_generator": {
        "engine": "Vulnogram 0.1.0-dev"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
    "assignerShortName": "wolfSSL",
    "cveId": "CVE-2023-6936",
    "datePublished": "2024-02-20T21:52:02.441Z",
    "dateReserved": "2023-12-18T22:01:24.437Z",
    "dateUpdated": "2025-03-26T16:28:30.322Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2023-6936",
      "date": "2026-10-20",
      "epss": "0.006",
      "percentile": "0.47759"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "modules": [
                  "TLS"
                ],
                "product": "wolfSSL",
                "repo": "https://github.com/wolfSSL/wolfssl",
                "vendor": "wolfSSL",
                "versions": [
                  {
                    "lessThanOrEqual": "5.6.5",
                    "status": "affected",
                    "version": "0",
                    "versionType": "release bundle"
                  }
                ]
              }
            ],
            "source": "facts@wolfssl.com"
          },
          {
            "affectedData": [
              {
                "cpes": [
                  "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*"
                ],
                "defaultStatus": "unknown",
                "product": "wolfssl",
                "vendor": "wolfssl",
                "versions": [
                  {
                    "lessThanOrEqual": "5.6.5",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              }
            ],
            "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "57DCDF61-F982-41D7-83BE-DDAEC85A797A",
                    "versionEndExcluding": "5.6.6",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\n"
          },
          {
            "lang": "es",
            "value": "En wolfSSL anterior a 5.6.6, si las funciones de devoluci\u00f3n de llamada est\u00e1n habilitadas (a trav\u00e9s del indicador WOLFSSL_CALLBACKS), entonces un cliente TLS malicioso o un atacante de red puede desencadenar una sobrelectura del b\u00fafer en el mont\u00f3n de 5 bytes (WOLFSSL_CALLBACKS solo est\u00e1 destinado a la depuraci\u00f3n)."
          }
        ],
        "id": "CVE-2023-6936",
        "lastModified": "2026-06-17T06:51:43.160",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 5.3,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 1.4,
              "source": "facts@wolfssl.com",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 9.1,
                "baseSeverity": "CRITICAL",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 5.2,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2023-6936",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "yes"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-08-27T14:22:41.353325Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2024-02-20T22:15:08.197",
        "references": [
          {
            "source": "facts@wolfssl.com",
            "tags": [
              "Issue Tracking",
              "Patch"
            ],
            "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
          },
          {
            "source": "facts@wolfssl.com",
            "tags": [
              "Vendor Advisory"
            ],
            "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Issue Tracking",
              "Patch"
            ],
            "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
          },
          {
            "source": "af854a3a-2127-422b-91ae-364da2661108",
            "tags": [
              "Vendor Advisory"
            ],
            "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
          }
        ],
        "sourceIdentifier": "facts@wolfssl.com",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-125"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          },
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-126"
              }
            ],
            "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "current_release_date": "2025-05-28T22:44:33+00:00",
      "cve": "CVE-2023-6936",
      "id": "CVE-2023-6936",
      "initial_release_date": "2023-12-20T00:00:00+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "Heap-buffer over-read with WOLFSSL_CALLBACKS",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2023/cve-2023-6936.json",
      "version": "3"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "providerMetadata": {
              "dateUpdated": "2024-08-02T08:42:08.671Z",
              "orgId": "af854a3a-2127-422b-91ae-364da2661108",
              "shortName": "CVE"
            },
            "references": [
              {
                "tags": [
                  "patch",
                  "x_transferred"
                ],
                "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
              },
              {
                "tags": [
                  "vendor-advisory",
                  "x_transferred"
                ],
                "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
              }
            ],
            "title": "CVE Program Container"
          },
          {
            "affected": [
              {
                "cpes": [
                  "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*"
                ],
                "defaultStatus": "unknown",
                "product": "wolfssl",
                "vendor": "wolfssl",
                "versions": [
                  {
                    "lessThanOrEqual": "5.6.5",
                    "status": "affected",
                    "version": "0",
                    "versionType": "custom"
                  }
                ]
              }
            ],
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2023-6936",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2024-08-27T14:22:41.353325Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "problemTypes": [
              {
                "descriptions": [
                  {
                    "cweId": "CWE-126",
                    "description": "CWE-126 Buffer Over-read",
                    "lang": "en",
                    "type": "CWE"
                  }
                ]
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2024-07-05T15:20:37.482Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "modules": [
                "TLS"
              ],
              "product": "wolfSSL",
              "repo": "https://github.com/wolfSSL/wolfssl",
              "vendor": "wolfSSL",
              "versions": [
                {
                  "lessThanOrEqual": "5.6.5",
                  "status": "affected",
                  "version": "0",
                  "versionType": "release bundle"
                }
              ]
            }
          ],
          "configurations": [
            {
              "lang": "en",
              "supportingMedia": [
                {
                  "base64": false,
                  "type": "text/html",
                  "value": "To be vulnerable, wolfSSL callback functionality (which includes handshake and timeout callback functionality) must must be enabled with:\u003cbr\u003e\u003cb\u003e\u003cspan style=\"background-color: transparent;\"\u003eCFLAGS=\"-DWOLFSSL_CALLBACKS\"\u003c/span\u003e\u003c/b\u003e\u003cbr\u003e\u003cbr\u003eThis option is disabled by default. The default configuration of wolfSSL is not vulnerable."
                }
              ],
              "value": "To be vulnerable, wolfSSL callback functionality (which includes handshake and timeout callback functionality) must must be enabled with:\nCFLAGS=\"-DWOLFSSL_CALLBACKS\"\n\nThis option is disabled by default. The default configuration of wolfSSL is not vulnerable."
            }
          ],
          "credits": [
            {
              "lang": "en",
              "type": "finder",
              "user": "00000000-0000-4000-9000-000000000000",
              "value": "Lucca Hirschi (Inria, LORIA)"
            },
            {
              "lang": "en",
              "type": "finder",
              "user": "00000000-0000-4000-9000-000000000000",
              "value": "Steve Kremer (Inria, LORIA)"
            },
            {
              "lang": "en",
              "type": "finder",
              "user": "00000000-0000-4000-9000-000000000000",
              "value": "Max Ammann (Trail of Bits)"
            },
            {
              "lang": "en",
              "type": "tool",
              "user": "00000000-0000-4000-9000-000000000000",
              "value": "tlspuffin"
            }
          ],
          "datePublic": "2023-12-20T00:00:00.000Z",
          "descriptions": [
            {
              "lang": "en",
              "supportingMedia": [
                {
                  "base64": false,
                  "type": "text/html",
                  "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\u003cbr\u003e"
                }
              ],
              "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\n"
            }
          ],
          "metrics": [
            {
              "cvssV3_1": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 5.3,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
                "version": "3.1"
              },
              "format": "CVSS",
              "scenarios": [
                {
                  "lang": "en",
                  "value": "GENERAL"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2024-02-20T21:52:02.441Z",
            "orgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
            "shortName": "wolfSSL"
          },
          "references": [
            {
              "tags": [
                "patch"
              ],
              "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
            },
            {
              "tags": [
                "vendor-advisory"
              ],
              "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
            }
          ],
          "solutions": [
            {
              "lang": "en",
              "supportingMedia": [
                {
                  "base64": false,
                  "type": "text/html",
                  "value": "\u003cp\u003e\u003cspan style=\"background-color: transparent;\"\u003eThe fix for this issue is located in the following GitHub Pull Request: \u003c/span\u003e\u003ca target=\"_blank\" rel=\"nofollow\" href=\"https://github.com/wolfSSL/wolfssl/pull/6949/\"\u003ehttps://github.com/wolfSSL/wolfssl/pull/6949/\u003c/a\u003e\u003c/p\u003e"
                }
              ],
              "value": "The fix for this issue is located in the following GitHub Pull Request:  https://github.com/wolfSSL/wolfssl/pull/6949/ https://github.com/wolfSSL/wolfssl/pull/6949/ \n\n"
            }
          ],
          "source": {
            "discovery": "EXTERNAL"
          },
          "title": " Heap-buffer over-read with WOLFSSL_CALLBACKS",
          "workarounds": [
            {
              "lang": "en",
              "supportingMedia": [
                {
                  "base64": false,
                  "type": "text/html",
                  "value": "\u003cli\u003eDo not build wolfSSL with \u003cb\u003eWOLFSSL_CALLBACKS\u003c/b\u003e defined\u003c/li\u003e"
                }
              ],
              "value": "  *  Do not build wolfSSL with WOLFSSL_CALLBACKS defined\n"
            }
          ],
          "x_generator": {
            "engine": "Vulnogram 0.1.0-dev"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "50d2cd11-d01a-48ed-9441-5bfce9d63b27",
        "assignerShortName": "wolfSSL",
        "cveId": "CVE-2023-6936",
        "datePublished": "2024-02-20T21:52:02.441Z",
        "dateReserved": "2023-12-18T22:01:24.437Z",
        "dateUpdated": "2025-03-26T16:28:30.322Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}

CNVD-2024-37452

Vulnerability from cnvd - Published: 2024-09-05

Title

wolfSSL存在未明漏洞（CNVD-2024-37452）

Description

wolfSSL（CyaSSL）是美国wolfSSL公司的一个针对嵌入式系统开发人员使用的小的、可移植的嵌入式SSL编程库。 wolfSSL 5.6.6之前版本存在安全漏洞，攻击者可利用该漏洞触发5字节的缓冲区越界读取。

Severity

中

Patch Name

wolfSSL存在未明漏洞（CNVD-2024-37452）的补丁

Patch Description

wolfSSL（CyaSSL）是美国wolfSSL公司的一个针对嵌入式系统开发人员使用的小的、可移植的嵌入式SSL编程库。 wolfSSL 5.6.6之前版本存在安全漏洞，攻击者可利用该漏洞触发5字节的缓冲区越界读取。目前，供应商发布了安全公告及相关补丁信息，修复了此漏洞。

Formal description

厂商已发布了漏洞修复程序，请及时关注更新： https://github.com/wolfSSL/wolfssl/pull/6949/

Reference

https://www.wolfssl.com/docs/security-vulnerabilities/

Impacted products

Name
wolfSSL Inc. WolfSSL <5.6.6

Show details on source website

JSON

To clipboard

{
  "cves": {
    "cve": {
      "cveNumber": "CVE-2023-6936",
      "cveUrl": "https://nvd.nist.gov/vuln/detail/CVE-2023-6936"
    }
  },
  "description": "wolfSSL\uff08CyaSSL\uff09\u662f\u7f8e\u56fdwolfSSL\u516c\u53f8\u7684\u4e00\u4e2a\u9488\u5bf9\u5d4c\u5165\u5f0f\u7cfb\u7edf\u5f00\u53d1\u4eba\u5458\u4f7f\u7528\u7684\u5c0f\u7684\u3001\u53ef\u79fb\u690d\u7684\u5d4c\u5165\u5f0fSSL\u7f16\u7a0b\u5e93\u3002\n\nwolfSSL 5.6.6\u4e4b\u524d\u7248\u672c\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u89e6\u53d15\u5b57\u8282\u7684\u7f13\u51b2\u533a\u8d8a\u754c\u8bfb\u53d6\u3002",
  "formalWay": "\u5382\u5546\u5df2\u53d1\u5e03\u4e86\u6f0f\u6d1e\u4fee\u590d\u7a0b\u5e8f\uff0c\u8bf7\u53ca\u65f6\u5173\u6ce8\u66f4\u65b0\uff1a\r\nhttps://github.com/wolfSSL/wolfssl/pull/6949/",
  "isEvent": "\u901a\u7528\u8f6f\u786c\u4ef6\u6f0f\u6d1e",
  "number": "CNVD-2024-37452",
  "openTime": "2024-09-05",
  "patchDescription": "wolfSSL\uff08CyaSSL\uff09\u662f\u7f8e\u56fdwolfSSL\u516c\u53f8\u7684\u4e00\u4e2a\u9488\u5bf9\u5d4c\u5165\u5f0f\u7cfb\u7edf\u5f00\u53d1\u4eba\u5458\u4f7f\u7528\u7684\u5c0f\u7684\u3001\u53ef\u79fb\u690d\u7684\u5d4c\u5165\u5f0fSSL\u7f16\u7a0b\u5e93\u3002\r\n\r\nwolfSSL 5.6.6\u4e4b\u524d\u7248\u672c\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e\uff0c\u653b\u51fb\u8005\u53ef\u5229\u7528\u8be5\u6f0f\u6d1e\u89e6\u53d15\u5b57\u8282\u7684\u7f13\u51b2\u533a\u8d8a\u754c\u8bfb\u53d6\u3002\u76ee\u524d\uff0c\u4f9b\u5e94\u5546\u53d1\u5e03\u4e86\u5b89\u5168\u516c\u544a\u53ca\u76f8\u5173\u8865\u4e01\u4fe1\u606f\uff0c\u4fee\u590d\u4e86\u6b64\u6f0f\u6d1e\u3002",
  "patchName": "wolfSSL\u5b58\u5728\u672a\u660e\u6f0f\u6d1e\uff08CNVD-2024-37452\uff09\u7684\u8865\u4e01",
  "products": {
    "product": "wolfSSL Inc. WolfSSL \u003c5.6.6"
  },
  "referenceLink": "https://www.wolfssl.com/docs/security-vulnerabilities/",
  "serverity": "\u4e2d",
  "submitTime": "2024-03-14",
  "title": "wolfSSL\u5b58\u5728\u672a\u660e\u6f0f\u6d1e\uff08CNVD-2024-37452\uff09"
}

FKIE_CVE-2023-6936

Vulnerability from fkie_nvd - Published: 2024-02-20 22:15 - Updated: 2026-06-17 06:51

Severity

5.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Summary

References

URL	Tags
facts@wolfssl.com	https://github.com/wolfSSL/wolfssl/pull/6949/	Issue Tracking, Patch
facts@wolfssl.com	https://www.wolfssl.com/docs/security-vulnerabilities/	Vendor Advisory
af854a3a-2127-422b-91ae-364da2661108	https://github.com/wolfSSL/wolfssl/pull/6949/	Issue Tracking, Patch
af854a3a-2127-422b-91ae-364da2661108	https://www.wolfssl.com/docs/security-vulnerabilities/	Vendor Advisory

Impacted products

	Vendor	Product	Version
	wolfssl	wolfssl	*

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "modules": [
            "TLS"
          ],
          "product": "wolfSSL",
          "repo": "https://github.com/wolfSSL/wolfssl",
          "vendor": "wolfSSL",
          "versions": [
            {
              "lessThanOrEqual": "5.6.5",
              "status": "affected",
              "version": "0",
              "versionType": "release bundle"
            }
          ]
        }
      ],
      "source": "facts@wolfssl.com"
    },
    {
      "affectedData": [
        {
          "cpes": [
            "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*"
          ],
          "defaultStatus": "unknown",
          "product": "wolfssl",
          "vendor": "wolfssl",
          "versions": [
            {
              "lessThanOrEqual": "5.6.5",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "57DCDF61-F982-41D7-83BE-DDAEC85A797A",
              "versionEndExcluding": "5.6.6",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\n"
    },
    {
      "lang": "es",
      "value": "En wolfSSL anterior a 5.6.6, si las funciones de devoluci\u00f3n de llamada est\u00e1n habilitadas (a trav\u00e9s del indicador WOLFSSL_CALLBACKS), entonces un cliente TLS malicioso o un atacante de red puede desencadenar una sobrelectura del b\u00fafer en el mont\u00f3n de 5 bytes (WOLFSSL_CALLBACKS solo est\u00e1 destinado a la depuraci\u00f3n)."
    }
  ],
  "id": "CVE-2023-6936",
  "lastModified": "2026-06-17T06:51:43.160",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 5.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "LOW",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 1.4,
        "source": "facts@wolfssl.com",
        "type": "Secondary"
      },
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.1,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.2,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2023-6936",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2024-08-27T14:22:41.353325Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2024-02-20T22:15:08.197",
  "references": [
    {
      "source": "facts@wolfssl.com",
      "tags": [
        "Issue Tracking",
        "Patch"
      ],
      "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
    },
    {
      "source": "facts@wolfssl.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Issue Tracking",
        "Patch"
      ],
      "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
    }
  ],
  "sourceIdentifier": "facts@wolfssl.com",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        }
      ],
      "source": "nvd@nist.gov",
      "type": "Primary"
    },
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-126"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}

GHSA-CWPG-8775-J56V

Vulnerability from github – Published: 2024-02-21 00:31 – Updated: 2025-02-12 18:31

Details

Severity

5.3 (Medium)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2023-6936"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125",
      "CWE-126"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-02-20T22:15:08Z",
    "severity": "MODERATE"
  },
  "details": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).",
  "id": "GHSA-cwpg-8775-j56v",
  "modified": "2025-02-12T18:31:27Z",
  "published": "2024-02-21T00:31:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-6936"
    },
    {
      "type": "WEB",
      "url": "https://github.com/wolfSSL/wolfssl/pull/6949"
    },
    {
      "type": "WEB",
      "url": "https://www.wolfssl.com/docs/security-vulnerabilities"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    }
  ]
}

GSD-2023-6936

Vulnerability from gsd - Updated: 2023-12-19 06:01

Details

Aliases

CVE-2023-6936

JSON

To clipboard

{
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "aliases": [
        "CVE-2023-6936"
      ],
      "details": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\n",
      "id": "GSD-2023-6936",
      "modified": "2023-12-19T06:01:18.059345Z",
      "schema_version": "1.4.0"
    }
  },
  "namespaces": {
    "cve.org": {
      "CVE_data_meta": {
        "ASSIGNER": "facts@wolfssl.com",
        "ID": "CVE-2023-6936",
        "STATE": "PUBLIC"
      },
      "affects": {
        "vendor": {
          "vendor_data": [
            {
              "product": {
                "product_data": [
                  {
                    "product_name": "wolfSSL",
                    "version": {
                      "version_data": [
                        {
                          "version_affected": "\u003c=",
                          "version_name": "0",
                          "version_value": "5.6.5"
                        }
                      ]
                    }
                  }
                ]
              },
              "vendor_name": "wolfSSL"
            }
          ]
        }
      },
      "configuration": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "To be vulnerable, wolfSSL callback functionality (which includes handshake and timeout callback functionality) must must be enabled with:\u003cbr\u003e\u003cb\u003e\u003cspan style=\"background-color: transparent;\"\u003eCFLAGS=\"-DWOLFSSL_CALLBACKS\"\u003c/span\u003e\u003c/b\u003e\u003cbr\u003e\u003cbr\u003eThis option is disabled by default. The default configuration of wolfSSL is not vulnerable."
            }
          ],
          "value": "To be vulnerable, wolfSSL callback functionality (which includes handshake and timeout callback functionality) must must be enabled with:\nCFLAGS=\"-DWOLFSSL_CALLBACKS\"\n\nThis option is disabled by default. The default configuration of wolfSSL is not vulnerable."
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Lucca Hirschi (Inria, LORIA)"
        },
        {
          "lang": "en",
          "value": "Steve Kremer (Inria, LORIA)"
        },
        {
          "lang": "en",
          "value": "Max Ammann (Trail of Bits)"
        },
        {
          "lang": "en",
          "value": "tlspuffin"
        }
      ],
      "data_format": "MITRE",
      "data_type": "CVE",
      "data_version": "4.0",
      "description": {
        "description_data": [
          {
            "lang": "eng",
            "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\n"
          }
        ]
      },
      "generator": {
        "engine": "Vulnogram 0.1.0-dev"
      },
      "impact": {
        "cvss": [
          {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          }
        ]
      },
      "problemtype": {
        "problemtype_data": [
          {
            "description": [
              {
                "lang": "eng",
                "value": "n/a"
              }
            ]
          }
        ]
      },
      "references": {
        "reference_data": [
          {
            "name": "https://github.com/wolfSSL/wolfssl/pull/6949/",
            "refsource": "MISC",
            "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
          },
          {
            "name": "https://www.wolfssl.com/docs/security-vulnerabilities/",
            "refsource": "MISC",
            "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
          }
        ]
      },
      "solution": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cp\u003e\u003cspan style=\"background-color: transparent;\"\u003eThe fix for this issue is located in the following GitHub Pull Request: \u003c/span\u003e\u003ca target=\"_blank\" rel=\"nofollow\" href=\"https://github.com/wolfSSL/wolfssl/pull/6949/\"\u003ehttps://github.com/wolfSSL/wolfssl/pull/6949/\u003c/a\u003e\u003c/p\u003e"
            }
          ],
          "value": "The fix for this issue is located in the following GitHub Pull Request:  https://github.com/wolfSSL/wolfssl/pull/6949/ https://github.com/wolfSSL/wolfssl/pull/6949/ \n\n"
        }
      ],
      "source": {
        "discovery": "EXTERNAL"
      },
      "work_around": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "\u003cli\u003eDo not build wolfSSL with \u003cb\u003eWOLFSSL_CALLBACKS\u003c/b\u003e defined\u003c/li\u003e"
            }
          ],
          "value": "  *  Do not build wolfSSL with WOLFSSL_CALLBACKS defined\n"
        }
      ]
    },
    "nvd.nist.gov": {
      "cve": {
        "descriptions": [
          {
            "lang": "en",
            "value": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).\n"
          },
          {
            "lang": "es",
            "value": "En wolfSSL anterior a 5.6.6, si las funciones de devoluci\u00f3n de llamada est\u00e1n habilitadas (a trav\u00e9s del indicador WOLFSSL_CALLBACKS), entonces un cliente TLS malicioso o un atacante de red puede desencadenar una sobrelectura del b\u00fafer en el mont\u00f3n de 5 bytes (WOLFSSL_CALLBACKS solo est\u00e1 destinado a la depuraci\u00f3n)."
          }
        ],
        "id": "CVE-2023-6936",
        "lastModified": "2024-02-22T19:07:37.840",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "NONE",
                "baseScore": 5.3,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "LOW",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 1.4,
              "source": "facts@wolfssl.com",
              "type": "Secondary"
            }
          ]
        },
        "published": "2024-02-20T22:15:08.197",
        "references": [
          {
            "source": "facts@wolfssl.com",
            "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
          },
          {
            "source": "facts@wolfssl.com",
            "url": "https://www.wolfssl.com/docs/security-vulnerabilities/"
          }
        ],
        "sourceIdentifier": "facts@wolfssl.com",
        "vulnStatus": "Awaiting Analysis"
      }
    }
  }
}

MSRC_CVE-2023-6936

Vulnerability from csaf_microsoft - Published: 2024-02-02 08:00 - Updated: 2026-02-18 14:43

Summary

Heap-buffer over-read with WOLFSSL_CALLBACKS

Scope

1 vulnerability in this advisory, including CVE-2023-6936.

CVE-2023-6936

Known not affected: 2 products

Open the full advisory

UBUNTU-CVE-2023-6936 (CVE-2023-6936)

Vulnerability from osv_ubuntu – Published: 2024-02-20 22:15 – Updated: 2026-04-22 07:45 – Source website

Details

Severity

5.3 (Medium)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

9.1 (Critical)


                    
                      CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2023-6936	REPORT
	https://github.com/wolfSSL/wolfssl/blob/v5.6.6-st…	REPORT
	https://www.cve.org/CVERecord?id=CVE-2023-6936	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libcyassl5",
            "binary_version": "3.4.8+dfsg-1"
          },
          {
            "binary_name": "libwolfssl0",
            "binary_version": "3.4.8+dfsg-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:16.04:LTS",
        "name": "wolfssl",
        "purl": "pkg:deb/ubuntu/wolfssl@3.4.8+dfsg-1?arch=source\u0026distro=xenial"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.4.8+dfsg-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libwolfssl15",
            "binary_version": "3.13.0+dfsg-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "wolfssl",
        "purl": "pkg:deb/ubuntu/wolfssl@3.13.0+dfsg-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.10.2+dfsg-2",
        "3.12.0+dfsg-1",
        "3.12.2+dfsg-1",
        "3.13.0+dfsg-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libwolfssl24",
            "binary_version": "4.3.0+dfsg-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "wolfssl",
        "purl": "pkg:deb/ubuntu/wolfssl@4.3.0+dfsg-2?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.1.0+dfsg-2",
        "4.2.0+dfsg-1",
        "4.2.0+dfsg-2",
        "4.2.0+dfsg-3",
        "4.3.0+dfsg-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libwolfssl32",
            "binary_version": "5.2.0-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "wolfssl",
        "purl": "pkg:deb/ubuntu/wolfssl@5.2.0-2?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.6.0-3",
        "5.0.0-1",
        "5.1.1-1",
        "5.2.0-1",
        "5.2.0-2"
      ]
    }
  ],
  "aliases": [],
  "details": "In wolfSSL prior to 5.6.6, if callback functions are enabled (via the WOLFSSL_CALLBACKS flag), then a malicious TLS client or network attacker can trigger a buffer over-read on the heap of 5 bytes (WOLFSSL_CALLBACKS is only intended for debugging).",
  "id": "UBUNTU-CVE-2023-6936",
  "modified": "2026-04-22T07:45:11Z",
  "published": "2024-02-20T22:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2023-6936"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/wolfSSL/wolfssl/blob/v5.6.6-stable/ChangeLog.md#vulnerabilities"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-6936"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2023-6936"
  ]
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

Order JSON

Publication & reservation Sightings KEV catalogs Other timestamps

Loading timeline…

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

CVE-2023-6936 (GCVE-0-2023-6936)

CNVD-2024-37452

FKIE_CVE-2023-6936

GHSA-CWPG-8775-J56V

GSD-2023-6936

MSRC_CVE-2023-6936

UBUNTU-CVE-2023-6936 (CVE-2023-6936)

Tags

Sightings

Nomenclature

Vulnerability timeline

Related by attack behaviour