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

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                  "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"
                }
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              "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"
            }
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          "source": {
            "discovery": "EXTERNAL"
          },
          "title": " Heap-buffer over-read with WOLFSSL_CALLBACKS",
          "workarounds": [
            {
              "lang": "en",
              "supportingMedia": [
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                  "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"
        }
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    ]
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  "published": "2024-02-20T22:15:08.197",
  "references": [
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      "source": "facts@wolfssl.com",
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        "Patch"
      ],
      "url": "https://github.com/wolfSSL/wolfssl/pull/6949/"
    },
    {
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        "Vendor Advisory"
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    },
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      "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)"
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        }
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            "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": {
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      },
      "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"
          }
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      "problemtype": {
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            "description": [
              {
                "lang": "eng",
                "value": "n/a"
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      },
      "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

How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

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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)

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Nomenclature

Vulnerability timeline

Related by attack behaviour