{"id":"UBUNTU-CVE-2026-32792","details":"NLnet Labs Unbound 1.6.2 up to and including version 1.25.0 has a denial of service vulnerability when compiled with DNSCrypt support ('--enable-dnscrypt'). A bad DNSCrypt query could underflow Unbound's DNSCrypt packet reading procedure that may lead to heap overflow. A malicious actor can exploit the vulnerability with a single bad DNSCrypt query that its decrypted plaintext consists entirely of '0x00' bytes and does not contain the expected '0x80' marker. Unbound would then start reading more bytes than necessary until it finds a non-'0x00' byte. Based on the underlying memory allocator and the memory layout, it could lead to heap overflow while reading followed by a crash. Likelihood of a crash is low, since it relies heavily on the underlying memory allocator and the memory layout. If the heap overflow does not happen, Unbound's later packet checks will deny the packet. Unbound 1.25.1 contains a patch with a fix to bound reading in the given buffer space.","modified":"2026-06-02T20:15:11.121315880Z","published":"2026-05-20T00:00:00Z","related":["USN-8282-1"],"upstream":["CVE-2026-32792"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-32792"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-32792"},{"type":"REPORT","url":"https://nlnetlabs.nl/news/2026/May/20/unbound-1.25.1-released/"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8282-1"}],"affected":[{"package":{"name":"unbound","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.20-1","1.4.21-1","1.4.21-1ubuntu1","1.4.21-1ubuntu2","1.4.22-1ubuntu1","1.4.22-1ubuntu2","1.4.22-1ubuntu3","1.4.22-1ubuntu4","1.4.22-1ubuntu4.14.04.1","1.4.22-1ubuntu4.14.04.2","1.4.22-1ubuntu4.14.04.3","1.4.22-1ubuntu4.14.04.3+esm1","1.4.22-1ubuntu4.14.04.3+esm2","1.4.22-1ubuntu4.14.04.3+esm3"],"ecosystem_specific":{"binaries":[{"binary_name":"libunbound2","binary_version":"1.4.22-1ubuntu4.14.04.3+esm3"},{"binary_name":"python-unbound","binary_version":"1.4.22-1ubuntu4.14.04.3+esm3"},{"binary_name":"unbound","binary_version":"1.4.22-1ubuntu4.14.04.3+esm3"},{"binary_version":"1.4.22-1ubuntu4.14.04.3+esm3","binary_name":"unbound-anchor"},{"binary_name":"unbound-host","binary_version":"1.4.22-1ubuntu4.14.04.3+esm3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}},{"package":{"name":"unbound","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=esm-infra-legacy%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.4.22-1ubuntu6","1.5.7-1ubuntu1","1.5.7-1ubuntu2","1.5.8-1ubuntu1","1.5.8-1ubuntu1.1","1.5.8-1ubuntu1.1+esm1","1.5.8-1ubuntu1.1+esm2","1.5.8-1ubuntu1.1+esm3"],"ecosystem_specific":{"binaries":[{"binary_name":"libunbound2","binary_version":"1.5.8-1ubuntu1.1+esm3"},{"binary_name":"python-unbound","binary_version":"1.5.8-1ubuntu1.1+esm3"},{"binary_name":"unbound","binary_version":"1.5.8-1ubuntu1.1+esm3"},{"binary_version":"1.5.8-1ubuntu1.1+esm3","binary_name":"unbound-anchor"},{"binary_name":"unbound-host","binary_version":"1.5.8-1ubuntu1.1+esm3"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}},{"package":{"name":"unbound","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=esm-infra%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6.5-1","1.6.7-1","1.6.7-1build1","1.6.7-1ubuntu1","1.6.7-1ubuntu2","1.6.7-1ubuntu2.1","1.6.7-1ubuntu2.2","1.6.7-1ubuntu2.3","1.6.7-1ubuntu2.4","1.6.7-1ubuntu2.5","1.6.7-1ubuntu2.6","1.6.7-1ubuntu2.6+esm2","1.6.7-1ubuntu2.6+esm3","1.6.7-1ubuntu2.6+esm4"],"ecosystem_specific":{"binaries":[{"binary_version":"1.6.7-1ubuntu2.6+esm4","binary_name":"libunbound2"},{"binary_version":"1.6.7-1ubuntu2.6+esm4","binary_name":"python-unbound"},{"binary_name":"python3-unbound","binary_version":"1.6.7-1ubuntu2.6+esm4"},{"binary_version":"1.6.7-1ubuntu2.6+esm4","binary_name":"unbound"},{"binary_version":"1.6.7-1ubuntu2.6+esm4","binary_name":"unbound-anchor"},{"binary_version":"1.6.7-1ubuntu2.6+esm4","binary_name":"unbound-host"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}},{"package":{"name":"unbound","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=esm-infra%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.9.0-2ubuntu1","1.9.0-2ubuntu2","1.9.4-2","1.9.4-2ubuntu1","1.9.4-2ubuntu1.1","1.9.4-2ubuntu1.2","1.9.4-2ubuntu1.3","1.9.4-2ubuntu1.4","1.9.4-2ubuntu1.5","1.9.4-2ubuntu1.6","1.9.4-2ubuntu1.8","1.9.4-2ubuntu1.9","1.9.4-2ubuntu1.11","1.9.4-2ubuntu1.11+esm1"],"ecosystem_specific":{"binaries":[{"binary_name":"libunbound8","binary_version":"1.9.4-2ubuntu1.11+esm1"},{"binary_version":"1.9.4-2ubuntu1.11+esm1","binary_name":"python-unbound"},{"binary_name":"python3-unbound","binary_version":"1.9.4-2ubuntu1.11+esm1"},{"binary_version":"1.9.4-2ubuntu1.11+esm1","binary_name":"unbound"},{"binary_name":"unbound-anchor","binary_version":"1.9.4-2ubuntu1.11+esm1"},{"binary_name":"unbound-host","binary_version":"1.9.4-2ubuntu1.11+esm1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}},{"package":{"name":"unbound","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.13.1-1ubuntu5.15"}]}],"versions":["1.13.1-1ubuntu1","1.13.1-1ubuntu3","1.13.1-1ubuntu5","1.13.1-1ubuntu5.1","1.13.1-1ubuntu5.2","1.13.1-1ubuntu5.3","1.13.1-1ubuntu5.4","1.13.1-1ubuntu5.5","1.13.1-1ubuntu5.7","1.13.1-1ubuntu5.8","1.13.1-1ubuntu5.10","1.13.1-1ubuntu5.11","1.13.1-1ubuntu5.12","1.13.1-1ubuntu5.13","1.13.1-1ubuntu5.14"],"ecosystem_specific":{"binaries":[{"binary_name":"libunbound8","binary_version":"1.13.1-1ubuntu5.15"},{"binary_version":"1.13.1-1ubuntu5.15","binary_name":"python3-unbound"},{"binary_name":"unbound","binary_version":"1.13.1-1ubuntu5.15"},{"binary_name":"unbound-anchor","binary_version":"1.13.1-1ubuntu5.15"},{"binary_version":"1.13.1-1ubuntu5.15","binary_name":"unbound-host"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}},{"package":{"name":"unbound","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.19.2-1ubuntu3.8"}]}],"versions":["1.17.1-2","1.18.0-2ubuntu1","1.18.0-2ubuntu2","1.19.1-1ubuntu1","1.19.2-1ubuntu1","1.19.2-1ubuntu3","1.19.2-1ubuntu3.1","1.19.2-1ubuntu3.2","1.19.2-1ubuntu3.3","1.19.2-1ubuntu3.4","1.19.2-1ubuntu3.5","1.19.2-1ubuntu3.6","1.19.2-1ubuntu3.7"],"ecosystem_specific":{"binaries":[{"binary_version":"1.19.2-1ubuntu3.8","binary_name":"libunbound8"},{"binary_name":"python3-unbound","binary_version":"1.19.2-1ubuntu3.8"},{"binary_version":"1.19.2-1ubuntu3.8","binary_name":"unbound"},{"binary_version":"1.19.2-1ubuntu3.8","binary_name":"unbound-anchor"},{"binary_name":"unbound-host","binary_version":"1.19.2-1ubuntu3.8"}],"availability":"No subscription required"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}},{"package":{"name":"unbound","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.22.0-2ubuntu2.3"}]}],"versions":["1.22.0-1ubuntu1","1.22.0-2ubuntu1","1.22.0-2ubuntu2","1.22.0-2ubuntu2.1","1.22.0-2ubuntu2.2"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libunbound8","binary_version":"1.22.0-2ubuntu2.3"},{"binary_name":"python3-unbound","binary_version":"1.22.0-2ubuntu2.3"},{"binary_name":"unbound","binary_version":"1.22.0-2ubuntu2.3"},{"binary_name":"unbound-anchor","binary_version":"1.22.0-2ubuntu2.3"},{"binary_version":"1.22.0-2ubuntu2.3","binary_name":"unbound-host"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}},{"package":{"name":"unbound","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/unbound?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.24.2-1ubuntu2.1"}]}],"versions":["1.22.0-2ubuntu2","1.22.0-2ubuntu4","1.24.2-1ubuntu1","1.24.2-1ubuntu2"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"libunbound8","binary_version":"1.24.2-1ubuntu2.1"},{"binary_version":"1.24.2-1ubuntu2.1","binary_name":"python3-unbound"},{"binary_name":"unbound","binary_version":"1.24.2-1ubuntu2.1"},{"binary_version":"1.24.2-1ubuntu2.1","binary_name":"unbound-anchor"},{"binary_version":"1.24.2-1ubuntu2.1","binary_name":"unbound-host"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-32792.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},{"type":"Ubuntu","score":"medium"}]}