CVE-2026-12245 (GCVE-0-2026-12245)

Vulnerability from cvelistv5 – Published: 2026-06-25 05:24 – Updated: 2026-06-25 12:42
VLAI
Title
Denial of DNS over TLS service by any DoT client
Summary
NSD from version 4.13.0 has a heap use-after-free bug in logging errors on TLS connections, causing a crash of the server process, which can be triggered trivially by sending a DNS query over a DoT connection, and closing the connection without reading the response.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-25 12:42 UTC
CWE
Assigner
NLnet Labs CNA
CNA scorecard B 82/100 over 73 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
NLnet Labs NSD Affected: 4.13.0 , < 4.14.3 (semver)
guessed Create a notification for this product.
Date Public
2026-06-25 00:00
Credits
Qifan Zhang from Palo Alto Networks
Show details on NVD website
To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-12245",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-25T12:42:22.635356Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-25T12:42:50.104Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "NSD",
          "vendor": "NLnet Labs",
          "versions": [
            {
              "lessThan": "4.14.3",
              "status": "affected",
              "version": "4.13.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Qifan Zhang from Palo Alto Networks"
        }
      ],
      "datePublic": "2026-06-25T00:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "NSD from version 4.13.0 has a heap use-after-free bug in logging errors on TLS connections, causing a crash of the server process, which can be triggered trivially by sending a DNS query over a DoT connection, and closing the connection without reading the response."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "Any client with access to the DoT port (853) can keep all iserve children in a crash-restart loop denying DoT service"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-416",
              "description": "CWE-416: Use After Free",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-25T05:24:18.620Z",
        "orgId": "206fc3a0-e175-490b-9eaa-a5738056c9f6",
        "shortName": "NLnet Labs"
      },
      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12245.txt"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "This issue is fixed starting with version 4.14.3."
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-05-28T00:00:00.000Z",
          "value": "Issue reported by Qifan Zhang"
        },
        {
          "lang": "en",
          "time": "2026-06-12T00:00:00.000Z",
          "value": "NLnet Labs shares patch"
        },
        {
          "lang": "en",
          "time": "2026-06-15T00:00:00.000Z",
          "value": "Qifan Zhang verifies patch"
        },
        {
          "lang": "en",
          "time": "2026-06-25T00:00:00.000Z",
          "value": "Fix released with version 4.14.3"
        }
      ],
      "title": "Denial of DNS over TLS service by any DoT client",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "206fc3a0-e175-490b-9eaa-a5738056c9f6",
    "assignerShortName": "NLnet Labs",
    "cveId": "CVE-2026-12245",
    "datePublished": "2026-06-25T05:24:18.620Z",
    "dateReserved": "2026-06-15T06:47:18.496Z",
    "dateUpdated": "2026-06-25T12:42:50.104Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-12245",
      "date": "2026-10-27",
      "epss": "0.0046",
      "percentile": "0.39701"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "NSD",
                "vendor": "NLnet Labs",
                "versions": [
                  {
                    "lessThan": "4.14.3",
                    "status": "affected",
                    "version": "4.13.0",
                    "versionType": "semver"
                  }
                ]
              }
            ],
            "source": "sep@nlnetlabs.nl"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:a:nlnetlabs:nsd:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "5CFD6DBF-22D2-4A34-8BF9-D013F53DCCA9",
                    "versionEndExcluding": "4.14.3",
                    "versionStartIncluding": "4.13.0",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "NSD from version 4.13.0 has a heap use-after-free bug in logging errors on TLS connections, causing a crash of the server process, which can be triggered trivially by sending a DNS query over a DoT connection, and closing the connection without reading the response."
          },
          {
            "lang": "es",
            "value": "NSD a partir de la versi\u00f3n 4.13.0 tiene un error de uso despu\u00e9s de liberaci\u00f3n en el heap al registrar errores en conexiones TLS, causando una ca\u00edda del proceso del servidor, que puede ser activado trivialmente enviando una consulta DNS a trav\u00e9s de una conexi\u00f3n DoT y cerrando la conexi\u00f3n sin leer la respuesta."
          }
        ],
        "id": "CVE-2026-12245",
        "lastModified": "2026-10-25T23:10:00.167",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 7.5,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ],
          "cvssMetricV40": [
            {
              "cvssData": {
                "Automatable": "NOT_DEFINED",
                "Recovery": "NOT_DEFINED",
                "Safety": "NOT_DEFINED",
                "attackComplexity": "LOW",
                "attackRequirements": "NONE",
                "attackVector": "NETWORK",
                "availabilityRequirement": "NOT_DEFINED",
                "baseScore": 8.7,
                "baseSeverity": "HIGH",
                "confidentialityRequirement": "NOT_DEFINED",
                "exploitMaturity": "NOT_DEFINED",
                "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:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/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": "NONE",
                "vulnIntegrityImpact": "NONE",
                "vulnerabilityResponseEffort": "NOT_DEFINED"
              },
              "source": "sep@nlnetlabs.nl",
              "type": "Secondary"
            }
          ],
          "ssvcV203": [
            {
              "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "ssvcData": {
                "id": "CVE-2026-12245",
                "options": [
                  {
                    "exploitation": "none"
                  },
                  {
                    "automatable": "yes"
                  },
                  {
                    "technicalImpact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-25T12:42:22.635356Z",
                "version": "2.0.3"
              }
            }
          ]
        },
        "published": "2026-06-25T07:16:45.080",
        "references": [
          {
            "source": "sep@nlnetlabs.nl",
            "tags": [
              "Patch",
              "Vendor Advisory"
            ],
            "url": "https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12245.txt"
          }
        ],
        "sourceIdentifier": "sep@nlnetlabs.nl",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-416"
              }
            ],
            "source": "sep@nlnetlabs.nl",
            "type": "Secondary"
          }
        ]
      }
    },
    "redhat_vex": {
      "current_release_date": "2026-06-29T14:03:34+00:00",
      "cve": "CVE-2026-12245",
      "id": "CVE-2026-12245",
      "initial_release_date": "2026-06-25T00:00:00+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "NSD: Denial of DNS over TLS service by any DoT client",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-12245.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-06-30T01:49:45Z",
      "cve": "CVE-2026-12245",
      "id": "CVE-2026-12245",
      "initial_release_date": "2026-06-30T01:49:45Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-12245",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-12245.json",
      "version": "2"
    },
    "vulnrichment": {
      "containers": {
        "adp": [
          {
            "metrics": [
              {
                "other": {
                  "content": {
                    "id": "CVE-2026-12245",
                    "options": [
                      {
                        "Exploitation": "none"
                      },
                      {
                        "Automatable": "yes"
                      },
                      {
                        "Technical Impact": "partial"
                      }
                    ],
                    "role": "CISA Coordinator",
                    "timestamp": "2026-06-25T12:42:22.635356Z",
                    "version": "2.0.3"
                  },
                  "type": "ssvc"
                }
              }
            ],
            "providerMetadata": {
              "dateUpdated": "2026-06-25T12:42:36.299Z",
              "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
              "shortName": "CISA-ADP"
            },
            "title": "CISA ADP Vulnrichment"
          }
        ],
        "cna": {
          "affected": [
            {
              "defaultStatus": "unaffected",
              "product": "NSD",
              "vendor": "NLnet Labs",
              "versions": [
                {
                  "lessThan": "4.14.3",
                  "status": "affected",
                  "version": "4.13.0",
                  "versionType": "semver"
                }
              ]
            }
          ],
          "credits": [
            {
              "lang": "en",
              "type": "finder",
              "value": "Qifan Zhang from Palo Alto Networks"
            }
          ],
          "datePublic": "2026-06-25T00:00:00.000Z",
          "descriptions": [
            {
              "lang": "en",
              "value": "NSD from version 4.13.0 has a heap use-after-free bug in logging errors on TLS connections, causing a crash of the server process, which can be triggered trivially by sending a DNS query over a DoT connection, and closing the connection without reading the response."
            }
          ],
          "metrics": [
            {
              "cvssV4_0": {
                "baseScore": 8.7,
                "baseSeverity": "HIGH",
                "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
                "version": "4.0"
              },
              "format": "CVSS",
              "scenarios": [
                {
                  "lang": "en",
                  "value": "Any client with access to the DoT port (853) can keep all iserve children in a crash-restart loop denying DoT service"
                }
              ]
            }
          ],
          "problemTypes": [
            {
              "descriptions": [
                {
                  "cweId": "CWE-416",
                  "description": "CWE-416: Use After Free",
                  "lang": "en",
                  "type": "CWE"
                }
              ]
            }
          ],
          "providerMetadata": {
            "dateUpdated": "2026-06-25T05:24:18.620Z",
            "orgId": "206fc3a0-e175-490b-9eaa-a5738056c9f6",
            "shortName": "NLnet Labs"
          },
          "references": [
            {
              "tags": [
                "vendor-advisory"
              ],
              "url": "https://www.nlnetlabs.nl/downloads/nsd/CVE-2026-12245.txt"
            }
          ],
          "solutions": [
            {
              "lang": "en",
              "value": "This issue is fixed starting with version 4.14.3."
            }
          ],
          "timeline": [
            {
              "lang": "en",
              "time": "2026-05-28T00:00:00.000Z",
              "value": "Issue reported by Qifan Zhang"
            },
            {
              "lang": "en",
              "time": "2026-06-12T00:00:00.000Z",
              "value": "NLnet Labs shares patch"
            },
            {
              "lang": "en",
              "time": "2026-06-15T00:00:00.000Z",
              "value": "Qifan Zhang verifies patch"
            },
            {
              "lang": "en",
              "time": "2026-06-25T00:00:00.000Z",
              "value": "Fix released with version 4.14.3"
            }
          ],
          "title": "Denial of DNS over TLS service by any DoT client",
          "x_generator": {
            "engine": "cvelib 1.8.0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "206fc3a0-e175-490b-9eaa-a5738056c9f6",
        "assignerShortName": "NLnet Labs",
        "cveId": "CVE-2026-12245",
        "datePublished": "2026-06-25T05:24:18.620Z",
        "dateReserved": "2026-06-15T06:47:18.496Z",
        "dateUpdated": "2026-06-25T12:42:50.104Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

JSON

Loading timeline…




    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.