{"id":"AZL-101712","summary":"CVE-2026-82720 affecting package unbound 1.26.0-1","details":"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.","modified":"2026-09-19T05:33:49Z","published":"2026-09-16T09:17:06Z","upstream":["CVE-2026-82720"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-82720"}],"affected":[{"package":{"name":"unbound","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/unbound"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"1.26.0-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-101712.json"}}],"schema_version":"1.9.0"}