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        "state": "PUBLISHED",
        "assignerShortName": "NLnet Labs",
        "dateReserved": "2026-09-07T14:06:21.960Z",
        "datePublished": "2026-09-16T08:32:10.359Z",
        "dateUpdated": "2026-09-16T14:14:25.720Z"
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            "title": "Use-after-free in DoH stream cleanup code path",
            "datePublic": "2026-09-16T00:00:00.000Z",
            "affected": [
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                    "vendor": "NLnet Labs",
                    "product": "Unbound",
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                            "version": "1.12.0",
                            "status": "affected",
                            "lessThan": "1.26.1",
                            "versionType": "semver"
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                    "lang": "en",
                    "value": "NLnet Labs Unbound 1.12.0 up to and including 1.26.0 has a use-after-free vulnerability when compiled for DNS-over-HTTPs support with '--with-libnghttp2'. During failure code paths (i.e., RPZ drop query, jostle due to heavy traffic), a dropped DoH stream brings down the whole DoH session and does not account properly for other DoH streams in the same session. This leads to use-after-free in those code paths. If the prerequisites are satisfied (possible RPZ drop or heavy client traffic), a malicious actor can trigger the vulnerability with a single DoH connection and the appropriate traffic. Impact is limited as the reads are not user controlled and the use-after-free leads to early returns. However, a hardened allocator can catch the use-after-free and controllably terminate the process resulting to denial of service."
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                            "description": "CWE-416: Use After Free",
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                    "lang": "en",
                    "value": "This issue is fixed starting with version 1.26.1"
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                {
                    "time": "2026-08-11T00:00:00.000Z",
                    "lang": "en",
                    "value": "Issue reported by Yuqi Qiu"
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                    "lang": "en",
                    "value": "NLnet Labs shares patch"
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                    "time": "2026-08-14T00:00:00.000Z",
                    "lang": "en",
                    "value": "Yuqi Qiu verifies patch"
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                    "time": "2026-09-16T00:00:00.000Z",
                    "lang": "en",
                    "value": "Fixes released with version 1.26.1"
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                    "lang": "en",
                    "value": "Yuqi Qiu (Nankai University, AOSP Lab)",
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                    "value": "Xiang Li (Nankai University, AOSP Lab)",
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                {
                    "url": "https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-82720.txt",
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