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              "content": {
                "id": "CVE-2026-40622",
                "options": [
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                    "Exploitation": "none"
                  },
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                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
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                ],
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                "timestamp": "2026-05-20T12:12:27.631955Z",
                "version": "2.0.3"
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        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-346",
                "description": "CWE-346 Origin Validation Error",
                "lang": "en",
                "type": "CWE"
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            ]
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        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-20T12:12:33.115Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
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    ],
    "cna": {
      "affected": [
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          "defaultStatus": "unaffected",
          "product": "Unbound",
          "vendor": "NLnet Labs",
          "versions": [
            {
              "lessThan": "1.25.1",
              "status": "affected",
              "version": "1.16.2",
              "versionType": "semver"
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          "lang": "en",
          "type": "finder",
          "value": "Qifan Zhang (Palo Alto Networks)"
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      "datePublic": "2026-05-20T00:00:00.000Z",
      "descriptions": [
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          "lang": "en",
          "value": "NLnet Labs Unbound 1.16.2 up to and including version 1.25.0 has a vulnerability of the \u0027ghost domain names\u0027 family of attacks that could extend the ghost domain window by up to one cached TTL configured value. Similar to other \u0027ghost domain names\u0027 attacks, an adversary needs to control a (ghost) zone and be able to query a vulnerable Unbound. A single client NS query can cause Unbound to overwrite the cached expired parent-side referral NS rrset with the child-side apex NS rrset and essentially extend the ghost domain window by up to one cached TTL configured value (\u0027cache-max-ttl\u0027). In configurations where \u0027harden-referral-path: yes\u0027 is used (non-default configuration), no client NS query is required since Unbound implicitly performs that query. Unbound 1.25.1 contains a patch with a fix that does not allow extension of TTLs for (parent) NS records regardless of their trust."
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            "baseSeverity": "MEDIUM",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Amber",
            "version": "4.0"
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          "scenarios": [
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              "lang": "en",
              "value": "GENERAL"
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        "dateUpdated": "2026-05-20T09:18:41.816Z",
        "orgId": "206fc3a0-e175-490b-9eaa-a5738056c9f6",
        "shortName": "NLnet Labs"
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      "references": [
        {
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-40622.txt"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "This issue is fixed starting with version 1.25.1"
        }
      ],
      "timeline": [
        {
          "lang": "en",
          "time": "2026-04-28T00:00:00.000Z",
          "value": "Issue reported by Qifan Zhang"
        },
        {
          "lang": "en",
          "time": "2026-05-07T00:00:00.000Z",
          "value": "NLnet Labs shares patch"
        },
        {
          "lang": "en",
          "time": "2026-05-08T00:00:00.000Z",
          "value": "Qifan Zhang verifies patch"
        },
        {
          "lang": "en",
          "time": "2026-05-20T00:00:00.000Z",
          "value": "Fixes released with version 1.25.1"
        }
      ],
      "title": "Another \u0027ghost domain names\u0027 attack variant",
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  "cveMetadata": {
    "assignerOrgId": "206fc3a0-e175-490b-9eaa-a5738056c9f6",
    "assignerShortName": "NLnet Labs",
    "cveId": "CVE-2026-40622",
    "datePublished": "2026-05-20T09:18:41.816Z",
    "dateReserved": "2026-05-07T10:07:51.817Z",
    "dateUpdated": "2026-05-20T12:12:33.115Z",
    "state": "PUBLISHED"
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