Quick answers
- Is CVE-2026-32936 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-32936 being exploited in the wild.
- How severe is CVE-2026-32936?
- High severity, with a CVSS score of 7.5, published 5 May 2026.
- Which products and versions are affected?
- CoreDNS < 1.14.3; github.com/coredns/coredns (Go) < 1.14.3, SEMVER:introduced=0,fixed=1.14.3.
- Is there a fix for CVE-2026-32936?
- Yes. github.com/coredns/coredns (Go): upgrade to 1.14.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-32936 attacked?
- It is attacked over the network, in a hosted service.
- Am I affected by CVE-2026-32936?
- Check whether you run CoreDNS or github.com/coredns/coredns (Go) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- github.com/coredns/coredns (Go): upgrade to 1.14.3 or later
go get github.com/coredns/coredns@v1.14.3
Technical details
A denial-of-service (DoS) vulnerability exists in CoreDNS versions prior to 1.14.3 within the DNS-over-HTTPS (DoH) GET request handler. While the POST path implements a bounded read using http.MaxBytesReader (limited to 64KB), the GET path lacks equivalent size validation for the 'dns=' query parameter. An unauthenticated remote attacker can send oversized base64-encoded DNS queries, forcing the server to perform URL unescaping, base64 decoding, and DNS message unpacking before the request is eventually rejected. This results in uncontrolled resource consumption (CWE-400), characterized by high CPU usage, large transient memory allocations, and increased garbage collection pressure. The issue is resolved in version 1.14.3 by implementing proper size checks on the GET path.
Affected products
- CoreDNS CoreDNS < 1.14.3
Identifiers
- CVE-2026-32936
- GHSA-63cw-r7xf-jmwr
- GO-2026-5164
Timeline
- 2026-04-22: patched: Version 1.14.3 released
- 2026-04-25: advisory: GitHub Security Advisory GHSA-63cw-r7xf-jmwr published
- 2026-05-05: disclosed: CVE-2026-32936 published to NVD