{"id":"AZL-92952","summary":"CVE-2026-32665 affecting package unbound for versions less than 1.25.2-1","details":"In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, when downstream DNS-over-QUIC (DoQ) is enabled, the first two bidirectional streams on a new QUIC connection (stream_id 0 and 4) bypass the per-stream 'quic-size' gate entirely, and large input buffers are allocated later, after only the 2-byte length prefix has been received from the initial streams. As a result, a remote client can make Unbound exceed the configured 'quic-size' limit with low-cost input. Using only one connection and two streams, each sending a declared 65535-byte length prefix and then holding the streams open, a client can already trivially make Unbound roughly allocate double that amount. This is a remote availability issue / memory-accounting bypass in the downstream DoQ implementation that leads to denial of service for new DoQ clients. This vulnerability needs Unbound to be compiled with DoQ support ('--with-libngtcp2') and the 'quic-port' to be configured for the listening interfaces.","modified":"2026-08-28T17:47:35.926808013Z","published":"2026-07-22T14:17:18Z","upstream":["CVE-2026-32665"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-32665"}],"affected":[{"package":{"name":"unbound","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/unbound"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.25.2-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-92952.json"}}],"schema_version":"1.9.0"}