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High DSA-5987-1 3 CVEs

unbound - security update

Published Aug 27, 2025 · Updated Mar 9, 2026

Ecosystem: Debian

Fixed packages 1

ReleasePackageFixed in
Debian · 12 unbound 1.17.1-2+deb12u3

Vulnerabilities 3

  • High 8.7
    CVE-2025-5994

    Cache poisoning via the ECS-enabled Rebirthday Attack

    A multi-vendor cache poisoning vulnerability named 'Rebirthday Attack' has been discovered in caching resolvers that support EDNS Client Subnet (ECS). Unbound is also vulnerable when compiled with ECS support, i.e., '--enable-subnet', AND configured to send E…

    NLnet Labs Unbound unbound unbound Debian Ubuntu Alpine
  • High 7.5
    CVE-2024-33655

    The DNS protocol in RFC 1035 and updates allows remote attackers to cause a denial of service (resource consumption) by…

    unbound unbound unbound unbound Debian Ubuntu Azure Linux Alpine
  • Medium 5.3
    CVE-2024-8508

    Unbounded name compression could lead to Denial of Service

    NLnet Labs Unbound up to and including version 1.21.0 contains a vulnerability when handling replies with very large RRsets that it needs to perform name compression for. Malicious upstreams responses with very large RRsets can cause Unbound to spend a consid…

    NLnet Labs Unbound unbound unbound Debian Ubuntu Azure Linux Alpine