CVE-2025-58063 is a high-severity (CVSS 7.1) CWE-681 vulnerability in github.com/coredns/coredns. O3 Security confirms whether CVE-2025-58063 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
CoreDNS: DNS Cache Pinning via etcd Lease ID Confusion
Real-World Exposure
github.com/coredns/corednsReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
CoreDNS is a DNS server that chains plugins. Starting in version 1.2.0 and prior to version 1.12.4, the CoreDNS etcd plugin contains a TTL confusion vulnerability where lease IDs are incorrectly used as TTL values, enabling DNS cache pinning attacks. This effectively creates a DoS condition for DNS resolution of affected services. The TTL() function in plugin/etcd/etcd.go incorrectly casts etcd lease IDs (64-bit integers) to uint32 and uses them as TTL values. Large lease IDs become very large TTLs when cast to uint32. This enables cache pinning attacks. Version 1.12.4 contains a fix for the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/coredns/coredns | ≥ 1.2.0&&< 1.12.4 | 1.12.4 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/coredns/coredns. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/coredns/coredns to 1.12.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-58063 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2025-58063 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2025-58063. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-58063 in your dependencies?
O3 detects CVE-2025-58063 across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.