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.
No analysis available yet.
Remediation
No remediation available yet.
Tracking
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Advisories
| Source | ID | Title |
|---|---|---|
Github GHSA |
GHSA-63cw-r7xf-jmwr | CoreDNS DoH GET oversized dns= query parameter causes pre-validation CPU and memory amplification |
References
History
Tue, 05 May 2026 20:15:00 +0000
| Type | Values Removed | Values Added |
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| Metrics |
ssvc
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Tue, 05 May 2026 19:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | CoreDNS DoH GET path missing size validation causes CPU and memory amplification | |
| Weaknesses | CWE-400 | |
| References |
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| Metrics |
cvssV4_0
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Subscriptions
No data.
Status: PUBLISHED
Assigner: GitHub_M
Published:
Updated: 2026-05-05T19:32:25.341Z
Reserved: 2026-03-17T00:05:53.282Z
Link: CVE-2026-32936
Updated: 2026-05-05T19:32:10.408Z
Status : Received
Published: 2026-05-05T20:16:36.010
Modified: 2026-05-05T20:16:36.010
Link: CVE-2026-32936
No data.
OpenCVE Enrichment
No data.
Weaknesses
Github GHSA