{"id":"CVE-2026-32936","summary":"CoreDNS DoH GET path missing size validation causes CPU and memory amplification","details":"CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the DNS-over-HTTPS (DoH) GET path accepts oversized dns= query parameter values and performs URL query parsing, base64 decoding, and DNS message unpacking before rejecting the request. Unlike the POST path, which applies a bounded read via http.MaxBytesReader limited to 65536 bytes, the GET path has no equivalent size validation before expensive processing. A remote, unauthenticated attacker can repeatedly send oversized DoH GET requests to force high CPU usage, large transient memory allocations, and elevated garbage-collection pressure, leading to denial of service. This issue has been fixed in version 1.14.3.","aliases":["GHSA-63cw-r7xf-jmwr"],"modified":"2026-05-28T03:53:05.039755299Z","published":"2026-05-05T19:07:51.926Z","related":["CGA-w5m8-x86h-7mrc","openSUSE-SU-2026:20703-1"],"database_specific":{"cwe_ids":["CWE-400"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/32xxx/CVE-2026-32936.json","cna_assigner":"GitHub_M"},"references":[{"type":"WEB","url":"https://github.com/coredns/coredns/releases/tag/v1.14.3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/32xxx/CVE-2026-32936.json"},{"type":"ADVISORY","url":"https://github.com/coredns/coredns/security/advisories/GHSA-63cw-r7xf-jmwr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-32936"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/coredns/coredns","events":[{"introduced":"0"},{"fixed":"17fceec6d93fd1dde5ba6888c363f131ff6d647f"}]}],"versions":["v1.14.2","v1.14.1","v1.14.0","v1.13.2","v1.13.1","v1.13.0","v1.12.4","v1.12.3","v1.12.2","v1.12.1","v1.12.0","v1.11.4","v1.11.3","v1.11.1","v1.11.0","v1.10.1","v1.10.0","v1.9.4","v1.9.3","v1.9.2","v1.9.1","v1.9.0","v1.8.7","v1.8.6","v1.8.5","v1.8.4","v1.8.3","v1.8.2","v1.8.1","v1.8.0","v1.7.1","v1.7.0","v1.6.9","v1.6.8","v1.6.7","v1.6.6","v1.6.5","v1.6.4","v1.6.3","v1.6.2","v1.6.1","v1.6.0","v1.5.2","v1.5.1","v1.5.0","v1.4.0","v1.3.1","v1.3.0","v1.2.6","v1.2.5","v1.2.4","v1.2.3","v1.2.2","v1.2.1","v1.2.0","v1.1.4","v1.1.3","v1.1.2","v1.1.1","v1.1.0","v1.0.6","v1.0.5","v1.0.3","v1.0.2","v1.0.1","v1.0.0","v0.9.10","v0.9.9","v011","v010","v009","v008","v007","v006","v005","v004","v003","v002","v001"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-32936.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}