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

Vulnerability from cvelistv5 – Published: 2026-06-25 05:24 – Updated: 2026-06-25 05:24
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
CWE
Assigner
References
Impacted products
Vendor Product Version
NLnet Labs NSD Affected: 4.13.0 , < 4.14.3 (semver)
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": {
    "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": "2026-06-25T05:24:18.620Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}


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