# NLnet Labs Unbound vulnerabilities Source: https://junglewise.ai/threats/technologies/unbound Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats Updated: 9 November 2026, 03:07 UTC. Rebuilt every hour. Data: https://junglewise.ai/threats/technologies/unbound.json License: CC BY 4.0 with a link back Junglewise Threat Intelligence has tracked 46 vulnerabilities in NLnet Labs Unbound: 0 in the last 7 days and 11 in the last 90 days, 2 of them critical and 0 exploited in the wild. The most recent, CVE-2026-97206, was published on 21 October 2026. 4 vulnerabilities in the last four weeks, down 43% on the four before (7). 0 critical against 2. ## Counts - Last 7 days: 0 - Last 30 days: 4 - Last 90 days: 11 - All time: 46 (2 critical, 0 exploited in the wild) ## About NLnet Labs Unbound Unbound is a validating, recursive, caching DNS resolver designed for high performance and security. ## Latest NLnet Labs Unbound vulnerabilities - [CVE-2026-97206: NLnet Labs Unbound use-after-free in DNS-over-QUIC stream cleanup](https://junglewise.ai/threats/cve-2026-97206-nlnet-labs-unbound-1-22-0-up-to-and-including-version-1-26-1) (high, CVSS 7.5, published 21 Oct 2026) - [CVE-2026-96405: NLnet Labs Unbound DNS decompression CPU exhaustion](https://junglewise.ai/threats/cve-2026-96405-nlnet-labs-unbound-up-to-and-including-version-1-26-1-limits) (medium, CVSS 5.3, published 21 Oct 2026) - [CVE-2026-50106: NLnet Labs Unbound DNS validator bypass in DNSSEC validation](https://junglewise.ai/threats/cve-2026-50106-when-nlnet-labs-unbound-up-to-and-including-version-1-26-1-is) (medium, CVSS 6.5, published 21 Oct 2026) - [CVE-2026-109125: NLnet Labs Unbound cache side-channel in upstream source port probe](https://junglewise.ai/threats/cve-2026-109125-in-nlnet-labs-unbound-up-to-and-including-version-1-26-1-an) (medium, CVSS 5.3, published 21 Oct 2026) - [CVE-2026-85501: NLnet Labs Unbound DNS complexity attacks via ReTrap](https://junglewise.ai/threats/cve-2026-85501-nlnet-labs-unbound-dns-complexity-attacks-via-retrap) (medium, CVSS 5.3, published 16 Sep 2026) - [CVE-2026-82720: NLnet Labs Unbound use-after-free in DNS-over-HTTPs](https://junglewise.ai/threats/cve-2026-82720-nlnet-labs-unbound-use-after-free-in-dns-over-https) (medium, CVSS 5.9, published 16 Sep 2026) - [CVE-2026-82717: NLnet Labs Unbound heap buffer overflow in CNAME synthesis](https://junglewise.ai/threats/cve-2026-82717-nlnet-labs-unbound-heap-buffer-overflow-in-cname-synthesis) (critical, CVSS 9.8, published 16 Sep 2026) - [CVE-2026-81642: NLnet Labs Unbound DNSSEC validator buffer overflow](https://junglewise.ai/threats/cve-2026-81642-nlnet-labs-unbound-dnssec-validator-buffer-overflow) (critical, CVSS 9.8, published 16 Sep 2026) - [CVE-2026-81634: NLnet Labs Unbound heap buffer overflow in RRSet canonicalisation](https://junglewise.ai/threats/cve-2026-81634-nlnet-labs-unbound-heap-buffer-overflow-in-rrset-canonicalisation) (high, CVSS 7.5, published 16 Sep 2026) - [CVE-2026-78227: NLnet Labs Unbound use-after-free in DNS-over-QUIC](https://junglewise.ai/threats/cve-2026-78227-nlnet-labs-unbound-use-after-free-in-dns-over-quic) (medium, CVSS 6.5, published 16 Sep 2026) - [CVE-2026-77955: NLnet Labs Unbound ZONEMD check bypass in delegated zones](https://junglewise.ai/threats/cve-2026-77955-nlnet-labs-unbound-zonemd-check-bypass-in-delegated-zones) (medium, CVSS 4.4, published 16 Sep 2026) - [CVE-2026-56444: NLnet Labs Unbound resource exhaustion in serve-expired logic](https://junglewise.ai/threats/cve-2026-56444-nlnet-labs-unbound-resource-exhaustion-in-serve-expired-logic) (medium, CVSS 5.9, published 22 Jul 2026) - [CVE-2026-56416: NLnet Labs Unbound heap buffer overflow in DNSSEC validator](https://junglewise.ai/threats/cve-2026-56416-nlnet-labs-unbound-heap-buffer-overflow-in-dnssec-validator) (medium, CVSS 4.8, published 22 Jul 2026) - [CVE-2026-55991: NLnet Labs Unbound denial of service in DNS-over-QUIC](https://junglewise.ai/threats/cve-2026-55991-nlnet-labs-unbound-denial-of-service-in-dns-over-quic) (medium, CVSS 5.9, published 22 Jul 2026) - [CVE-2026-55990: NLnet Labs Unbound denial of service in DNSCrypt](https://junglewise.ai/threats/cve-2026-55990-nlnet-labs-unbound-denial-of-service-in-dnscrypt) (medium, CVSS 5.9, published 22 Jul 2026) - [CVE-2026-55973: NLnet Labs Unbound stack overflow in DNS error reporting](https://junglewise.ai/threats/cve-2026-55973-nlnet-labs-unbound-stack-overflow-in-dns-error-reporting) (high, CVSS 7.5, published 22 Jul 2026) - [CVE-2026-55717: NLnet Labs Unbound DoS via NULL pointer dereference in serve-expired-client-timeout](https://junglewise.ai/threats/cve-2026-55717-nlnet-labs-unbound-dos-via-null-pointer-dereference-in-serve) (medium, CVSS 5.9, published 22 Jul 2026) - [CVE-2026-55708: NLnet Labs Unbound insecure default initialization in unbound-control](https://junglewise.ai/threats/cve-2026-55708-nlnet-labs-unbound-insecure-default-initialization-in-unbound) (low, CVSS 3.1, published 22 Jul 2026) - [CVE-2026-54478: NLnet Labs Unbound DNS Cookie authentication bypass in PROXYv2](https://junglewise.ai/threats/cve-2026-54478-nlnet-labs-unbound-dns-cookie-authentication-bypass-in-proxyv2) (low, CVSS 3.7, published 22 Jul 2026) - [CVE-2026-52863: NLnet Labs Unbound use-after-free in respip and dns64 modules](https://junglewise.ai/threats/cve-2026-52863-nlnet-labs-unbound-use-after-free-in-respip-and-dns64-modules) (medium, CVSS 5.9, published 22 Jul 2026) - [CVE-2026-50252: NLnet Labs Unbound DNS cache poisoning via predictable UDP source ports](https://junglewise.ai/threats/cve-2026-50252-nlnet-labs-unbound-dns-cache-poisoning-via-predictable-udp-source) (info, CVSS 5.7, published 22 Jul 2026) - [CVE-2026-50251: NLnet Labs Unbound cache flush via 0.0.0.0 glue records](https://junglewise.ai/threats/cve-2026-50251-nlnet-labs-unbound-cache-flush-via-0-0-0-0-glue-records) (medium, CVSS 5.3, published 22 Jul 2026) - [CVE-2026-50248: NLnet Labs Unbound insufficient verification of XFR endpoints in RPZ zones](https://junglewise.ai/threats/cve-2026-50248-nlnet-labs-unbound-insufficient-verification-of-xfr-endpoints-in) (medium, CVSS 6.5, published 22 Jul 2026) - [CVE-2026-50243: NLnet Labs Unbound DNSSEC validation bypass in respip module](https://junglewise.ai/threats/cve-2026-50243-nlnet-labs-unbound-dnssec-validation-bypass-in-respip-module) (info, CVSS 6.3, published 22 Jul 2026) - [CVE-2026-50046: NLnet Labs Unbound use-after-free in DNS-over-TLS forwarding](https://junglewise.ai/threats/cve-2026-50046-nlnet-labs-unbound-use-after-free-in-dns-over-tls-forwarding) (medium, CVSS 5.9, published 22 Jul 2026) ## Most severe NLnet Labs Unbound vulnerabilities - [CVE-2026-81642: NLnet Labs Unbound DNSSEC validator buffer overflow](https://junglewise.ai/threats/cve-2026-81642-nlnet-labs-unbound-dnssec-validator-buffer-overflow) (critical, CVSS 9.8, published 16 Sep 2026) - [CVE-2026-82717: NLnet Labs Unbound heap buffer overflow in CNAME synthesis](https://junglewise.ai/threats/cve-2026-82717-nlnet-labs-unbound-heap-buffer-overflow-in-cname-synthesis) (critical, CVSS 9.8, published 16 Sep 2026) - [CVE-2026-81634: NLnet Labs Unbound heap buffer overflow in RRSet canonicalisation](https://junglewise.ai/threats/cve-2026-81634-nlnet-labs-unbound-heap-buffer-overflow-in-rrset-canonicalisation) (high, CVSS 7.5, published 16 Sep 2026) - [CVE-2026-97206: NLnet Labs Unbound use-after-free in DNS-over-QUIC stream cleanup](https://junglewise.ai/threats/cve-2026-97206-nlnet-labs-unbound-1-22-0-up-to-and-including-version-1-26-1) (high, CVSS 7.5, published 21 Oct 2026) - [CVE-2026-55973: NLnet Labs Unbound stack overflow in DNS error reporting](https://junglewise.ai/threats/cve-2026-55973-nlnet-labs-unbound-stack-overflow-in-dns-error-reporting) (high, CVSS 7.5, published 22 Jul 2026) - [CVE-2026-44690: NLnet Labs Unbound cache poisoning via aggressive NSEC processing](https://junglewise.ai/threats/cve-2026-44690-nlnet-labs-unbound-cache-poisoning-via-aggressive-nsec-processing) (high, CVSS 7.5, published 22 Jul 2026) - [CVE-2026-40691: NLnet Labs Unbound heap overflow in DNSCrypt TCP handler](https://junglewise.ai/threats/cve-2026-40691-nlnet-labs-unbound-heap-overflow-in-dnscrypt-tcp-handler) (high, CVSS 7.5, published 22 Jul 2026) - [CVE-2026-32665: NLnet Labs Unbound denial of service in DNS-over-QUIC](https://junglewise.ai/threats/cve-2026-32665-nlnet-labs-unbound-denial-of-service-in-dns-over-quic) (high, CVSS 7.5, published 22 Jul 2026) - [CVE-2026-78227: NLnet Labs Unbound use-after-free in DNS-over-QUIC](https://junglewise.ai/threats/cve-2026-78227-nlnet-labs-unbound-use-after-free-in-dns-over-quic) (medium, CVSS 6.5, published 16 Sep 2026) - [CVE-2026-50106: NLnet Labs Unbound DNS validator bypass in DNSSEC validation](https://junglewise.ai/threats/cve-2026-50106-when-nlnet-labs-unbound-up-to-and-including-version-1-26-1-is) (medium, CVSS 6.5, published 21 Oct 2026) ## Vulnerabilities per week 4 vulnerabilities in the last four weeks, down 43% on the four before (7). 0 critical against 2. | Week of | Vulns | Critical | Exploited | | --- | --- | --- | --- | | 17 Aug 2026 | 0 | 0 | 0 | | 24 Aug 2026 | 0 | 0 | 0 | | 31 Aug 2026 | 0 | 0 | 0 | | 7 Sep 2026 | 0 | 0 | 0 | | 14 Sep 2026 | 7 | 2 | 0 | | 21 Sep 2026 | 0 | 0 | 0 | | 28 Sep 2026 | 0 | 0 | 0 | | 5 Oct 2026 | 0 | 0 | 0 | | 12 Oct 2026 | 0 | 0 | 0 | | 19 Oct 2026 | 4 | 0 | 0 | | 26 Oct 2026 | 0 | 0 | 0 | | 2 Nov 2026 | 0 | 0 | 0 | | 9 Nov 2026 | 0 | 0 | 0 | ## Other NLnet Labs technologies - [NLnet Labs Routinator](https://junglewise.ai/threats/technologies/routinator): 10 vulnerabilities - [NLnet Labs NSD](https://junglewise.ai/threats/technologies/nlnet-labs-nsd): 4 vulnerabilities - [NLnet Labs Krill](https://junglewise.ai/threats/technologies/krill): 3 vulnerabilities ## Sources NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories. Rebuilt every hour. Cite as: Junglewise Threat Intelligence, "NLnet Labs Unbound vulnerabilities", https://junglewise.ai/threats/technologies/unbound, 9 November 2026.