{"cve":"CVE-2026-32936","nvd":{"published":"2026-05-05T20:16:36.010","modified":"2026-07-25T11:10:00.100","status":"Analyzed","description":"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.","cvss_v4":{"vector":"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","score":8.7},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-400"],"references":["https://github.com/coredns/coredns/releases/tag/v1.14.3","https://github.com/coredns/coredns/security/advisories/GHSA-63cw-r7xf-jmwr","https://github.com/coredns/coredns/security/advisories/GHSA-63cw-r7xf-jmwr"],"products":["coredns.io:coredns"],"source":"nvd","synced_at":"2026-10-19T22:33:55.586217763+00:00"},"epss":{"cve":"CVE-2026-32936","score":0.00672,"percentile":0.52085,"date":"2026-10-31"},"kev":null,"osv":[{"id":"GHSA-63cw-r7xf-jmwr","url":"https://osv.dev/vulnerability/GHSA-63cw-r7xf-jmwr","summary":"CoreDNS DoH GET oversized dns= query parameter causes pre-validation CPU and memory amplification","modified":"2026-09-10T03:50:43.180023300Z","packages":[{"ecosystem":"Go","name":"github.com/coredns/coredns","purl":"pkg:golang/github.com/coredns/coredns","ranges":["<1.14.3"],"fixed":["1.14.3"]}]},{"id":"GO-2026-5164","url":"https://osv.dev/vulnerability/GO-2026-5164","summary":"CoreDNS DoH GET oversized dns= query parameter causes pre-validation CPU and memory amplification in github.com/coredns/coredns","modified":"2026-06-25T18:45:28.038992321Z","packages":[{"ecosystem":"Go","name":"github.com/coredns/coredns","purl":"pkg:golang/github.com/coredns/coredns","ranges":["<1.14.3"],"fixed":["1.14.3"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}