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        "state": "PUBLISHED",
        "assignerShortName": "NLnet Labs",
        "dateReserved": "2026-06-22T10:11:10.510Z",
        "datePublished": "2026-07-22T13:05:53.695Z",
        "dateUpdated": "2026-07-22T14:26:48.806Z"
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            "title": "Extra fix for CVE-2026-40622 to also clamp the TTL of A/AAAA records disallowing a one-time 'ghost domain' delegation renewal via glue records",
            "datePublic": "2026-07-22T00:00:00.000Z",
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                    "vendor": "NLnet Labs",
                    "product": "Unbound",
                    "versions": [
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                            "version": "1.16.2",
                            "status": "affected",
                            "lessThan": "1.25.2",
                            "versionType": "semver"
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                    "lang": "en",
                    "value": "In NLnet Labs Unbound 1.16.2 up to and including 1.25.1, a similar vulnerability as with CVE-2026-40622 in the 'ghost domain names' family of attacks was found in Unbound that could extend the ghost domain window by up to one cached TTL configured value for A/AAAA glue records. Similar to other 'ghost domain names' attacks, an adversary needs to control a (ghost) zone and be able to query a vulnerable Unbound. A single client A/AAAA query can cause Unbound to overwrite the cached expired parent-side glue rrset and essentially extend the ghost domain window by up to one cached TTL configured value ('cache-max-ttl'). In configurations where 'harden-referral-path: yes' is used (non-default configuration), no client query is required since Unbound implicitly performs that query. This is a variant of CVE-2026-40622 which only addressed the NS query."
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                            "description": "CWE-672: Operation on a Resource after Expiration or Release",
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            "solutions": [
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                    "lang": "en",
                    "value": "This issue is fixed starting with version 1.25.2"
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            "timeline": [
                {
                    "time": "2026-05-22T00:00:00.000Z",
                    "lang": "en",
                    "value": "Issue reported by Qifan Zhang"
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                    "time": "2026-06-10T00:00:00.000Z",
                    "lang": "en",
                    "value": "NLnet Labs shares patch"
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                    "time": "2026-06-13T00:00:00.000Z",
                    "lang": "en",
                    "value": "Qifan Zhang verifies patch"
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                    "time": "2026-07-22T00:00:00.000Z",
                    "lang": "en",
                    "value": "Fixes released with version 1.25.2"
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                    "value": "Qifan Zhang (Palo Alto Networks)",
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                    "url": "https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-42955.txt",
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