CVE-2026-26264 (GCVE-0-2026-26264)

Vulnerability from cvelistv5 – Published: 2026-02-13 18:14 – Updated: 2026-02-13 18:50
VLAI
Title
BACnet Stack WriteProperty decoding length underflow leads to OOB read and crash
Summary
BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.5.0rc4 and 1.4.3rc2, a malformed WriteProperty request can trigger a length underflow in the BACnet stack, leading to an out‑of‑bounds read and a crash (DoS). The issue is in wp.c within wp_decode_service_request. When decoding the optional priority context tag, the code passes apdu_len - apdu_size to bacnet_unsigned_context_decode without validating that apdu_size <= apdu_len. If a truncated APDU reaches this path, apdu_len - apdu_size underflows, resulting in a large size being used for decoding and an out‑of‑bounds read. This vulnerability is fixed in 1.5.0rc4 and 1.4.3rc2.
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-02-13 18:49 UTC
CWE
References
Impacted products
Vendor Product Version
bacnet-stack bacnet-stack Affected: >= 1.5.0rc1, < 1.5.0rc4
Affected: < 1.4.3rc2
Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-26264",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-02-13T18:49:44.498242Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-02-13T18:50:30.367Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "bacnet-stack",
          "vendor": "bacnet-stack",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 1.5.0rc1, \u003c 1.5.0rc4"
            },
            {
              "status": "affected",
              "version": "\u003c 1.4.3rc2"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.5.0rc4 and 1.4.3rc2, a malformed WriteProperty request can trigger a length underflow in the BACnet stack, leading to an out\u2011of\u2011bounds read and a crash (DoS). The issue is in wp.c within wp_decode_service_request. When decoding the optional priority context tag, the code passes apdu_len - apdu_size to bacnet_unsigned_context_decode without validating that apdu_size \u003c= apdu_len. If a truncated APDU reaches this path, apdu_len - apdu_size underflows, resulting in a large size being used for decoding and an out\u2011of\u2011bounds read. This vulnerability is fixed in 1.5.0rc4 and 1.4.3rc2."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:P",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-125",
              "description": "CWE-125: Out-of-bounds Read",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-02-13T18:14:30.232Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-phjh-v45p-gmjj",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-phjh-v45p-gmjj"
        },
        {
          "name": "https://github.com/bacnet-stack/bacnet-stack/commit/4cc8067c86f26e2b08b2c8f4d27f8e07de4d4708",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/bacnet-stack/bacnet-stack/commit/4cc8067c86f26e2b08b2c8f4d27f8e07de4d4708"
        }
      ],
      "source": {
        "advisory": "GHSA-phjh-v45p-gmjj",
        "discovery": "UNKNOWN"
      },
      "title": "BACnet Stack WriteProperty decoding length underflow leads to OOB read and crash"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-26264",
    "datePublished": "2026-02-13T18:14:30.232Z",
    "dateReserved": "2026-02-12T17:10:53.412Z",
    "dateUpdated": "2026-02-13T18:50:30.367Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-26264",
      "date": "2026-10-02",
      "epss": "0.00557",
      "percentile": "0.44463"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "product": "bacnet-stack",
                "vendor": "bacnet-stack",
                "versions": [
                  {
                    "status": "affected",
                    "version": "\u003e= 1.5.0rc1, \u003c 1.5.0rc4"
                  },
                  {
                    "status": "affected",
                    "version": "\u003c 1.4.3rc2"
                  }
                ]
              }
            ],
            "source": "security-advisories@github.com"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:bacnetstack:bacnet_stack:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "9BAD4B36-9061-453C-9C23-231993F1E69E",
                    "versionEndExcluding": "1.4.3",
                    "versionStartIncluding": "1.4.0",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:bacnetstack:bacnet_stack:1.4.3:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "F4D20F1C-637A-4398-AD64-43C05692782D",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "2B47182E-6B7F-4C53-904A-EB37C9C0A439",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "CF491863-1A31-4A23-A6AC-DF7545FCAA48",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:a:bacnetstack:bacnet_stack:1.5.0:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "DAB57C9E-9ABF-41FD-8D30-7C319ED23227",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.5.0rc4 and 1.4.3rc2, a malformed WriteProperty request can trigger a length underflow in the BACnet stack, leading to an out\u2011of\u2011bounds read and a crash (DoS). The issue is in wp.c within wp_decode_service_request. When decoding the optional priority context tag, the code passes apdu_len - apdu_size to bacnet_unsigned_context_decode without validating that apdu_size \u003c= apdu_len. If a truncated APDU reaches this path, apdu_len - apdu_size underflows, resulting in a large size being used for decoding and an out\u2011of\u2011bounds read. This vulnerability is fixed in 1.5.0rc4 and 1.4.3rc2."
          },
          {
            "lang": "es",
            "value": "BACnet Stack es una librer\u00eda C de pila de protocolo de c\u00f3digo abierto BACnet para sistemas embebidos. Antes de 1.5.0rc4 y 1.4.3rc2, una solicitud WriteProperty malformada puede desencadenar un desbordamiento negativo de longitud en la pila BACnet, lo que lleva a una lectura fuera de l\u00edmites y un fallo (DoS). El problema est\u00e1 en wp.c dentro de wp_decode_service_request. Al decodificar la etiqueta de contexto de prioridad opcional, el c\u00f3digo pasa apdu_len - apdu_size a bacnet_unsigned_context_decode sin validar que apdu_size \u0026lt;= apdu_len. Si una APDU truncada alcanza esta ruta, apdu_len - apdu_size sufre un desbordamiento negativo, lo que resulta en un tama\u00f1o grande siendo utilizado para la decodificaci\u00f3n y una lectura fuera de l\u00edmites. Esta vulnerabilidad est\u00e1 corregida en 1.5.0rc4 y 1.4.3rc2."
          }
        ],
        "id": "CVE-2026-26264",
        "lastModified": "2026-06-17T10:26:00.427",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 8.1,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 2.8,
              "impactScore": 5.2,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "cvssMetricV40": [
            {
              "cvssData": {
                "Automatable": "NOT_DEFINED",
                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
                "attackComplexity": "LOW",
                "attackRequirements": "NONE",
                "attackVector": "NETWORK",
                "availabilityRequirement": "NOT_DEFINED",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "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": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "NONE",
                "valueDensity": "NOT_DEFINED",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:H/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": "HIGH",
                "vulnConfidentialityImpact": "HIGH",
                "vulnIntegrityImpact": "NONE",
                "vulnerabilityResponseEffort": "NOT_DEFINED"
              },
              "source": "security-advisories@github.com",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-26264",
                "options": [
                  {
                    "exploitation": "poc"
                  },
                  {
                    "automatable": "yes"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-02-13T18:49:44.498242Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-02-13T19:17:31.143",
        "references": [
          {
            "source": "security-advisories@github.com",
            "tags": [
              "Patch"
            ],
            "url": "https://github.com/bacnet-stack/bacnet-stack/commit/4cc8067c86f26e2b08b2c8f4d27f8e07de4d4708"
          },
          {
            "source": "security-advisories@github.com",
            "tags": [
              "Exploit",
              "Vendor Advisory"
            ],
            "url": "https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-phjh-v45p-gmjj"
          }
        ],
        "sourceIdentifier": "security-advisories@github.com",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-125"
              }
            ],
            "source": "security-advisories@github.com",
            "type": "Secondary"
          }
        ]
      }
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-26264",
                    "options": [
                      {
                        "Exploitation": "poc"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-02-13T18:49:44.498242Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-02-13T18:50:05.321Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "product": "bacnet-stack",
              "vendor": "bacnet-stack",
              "versions": [
                {
                  "status": "affected",
                  "version": "\u003e= 1.5.0rc1, \u003c 1.5.0rc4"
                },
                {
                  "status": "affected",
                  "version": "\u003c 1.4.3rc2"
                }
              ]
            }
          ],
          "descriptions": [
            {
              "lang": "en",
              "value": "BACnet Stack is a BACnet open source protocol stack C library for embedded systems. Prior to 1.5.0rc4 and 1.4.3rc2, a malformed WriteProperty request can trigger a length underflow in the BACnet stack, leading to an out\u2011of\u2011bounds read and a crash (DoS). The issue is in wp.c within wp_decode_service_request. When decoding the optional priority context tag, the code passes apdu_len - apdu_size to bacnet_unsigned_context_decode without validating that apdu_size \u003c= apdu_len. If a truncated APDU reaches this path, apdu_len - apdu_size underflows, resulting in a large size being used for decoding and an out\u2011of\u2011bounds read. This vulnerability is fixed in 1.5.0rc4 and 1.4.3rc2."
            }
          ],
          "metrics": [
            {
              "cvssV4_0": {
                "attackComplexity": "LOW",
                "attackRequirements": "NONE",
                "attackVector": "NETWORK",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "privilegesRequired": "NONE",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "NONE",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:H/SC:N/SI:N/SA:N/E:P",
                "version": "4.0",
                "vulnAvailabilityImpact": "HIGH",
                "vulnConfidentialityImpact": "HIGH",
                "vulnIntegrityImpact": "NONE"
              }
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-125",
                  "description": "CWE-125: Out-of-bounds Read",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-02-13T18:14:30.232Z",
            "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
            "shortName": "GitHub_M"
          },
          "references": [
            {
              "name": "https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-phjh-v45p-gmjj",
              "tags": [
                "x_refsource_CONFIRM"
              ],
              "url": "https://github.com/bacnet-stack/bacnet-stack/security/advisories/GHSA-phjh-v45p-gmjj"
            },
            {
              "name": "https://github.com/bacnet-stack/bacnet-stack/commit/4cc8067c86f26e2b08b2c8f4d27f8e07de4d4708",
              "tags": [
                "x_refsource_MISC"
              ],
              "url": "https://github.com/bacnet-stack/bacnet-stack/commit/4cc8067c86f26e2b08b2c8f4d27f8e07de4d4708"
            }
          ],
          "source": {
            "advisory": "GHSA-phjh-v45p-gmjj",
            "discovery": "UNKNOWN"
          },
          "title": "BACnet Stack WriteProperty decoding length underflow leads to OOB read and crash"
        }
      },
      "cveMetadata": {
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "assignerShortName": "GitHub_M",
        "cveId": "CVE-2026-26264",
        "datePublished": "2026-02-13T18:14:30.232Z",
        "dateReserved": "2026-02-12T17:10:53.412Z",
        "dateUpdated": "2026-02-13T18:50:30.367Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.

Loading…

Loading…

Loading…

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.


Loading…