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 products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| coredns | coredns | >= 1.2.0, < 1.12.4 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | govulncheck-vulndb | 0.0.20250918T182144-150000.1.107.1 | SUSE-SU-2025:03289-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | coredns | 1.12.4-2.1 | openSUSE-SU-2025:15561-1 |
| openSUSE Tumbleweed | govulncheck-vulndb | 0.0.20250917T170349-1.1 | openSUSE-SU-2025:15564-1 |
| openSUSE Leap 16.0 | coredns | 1.14.0-bp160.1.1 | openSUSE-SU-2026:20099-1 |
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260723T184607-160000.1.1 | openSUSE-SU-2026:21483-1 |
| openSUSE Leap 15.6 | govulncheck-vulndb | 0.0.20250918T182144-150000.1.107.1 | SUSE-SU-2025:03289-1 |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | coredns | 1.11.4-10 | — |
| Azure Linux 2 (CBL-Mariner) | coredns | 1.11.1-22 | — |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | cloudflared | 2026.2.0-r0 | — |
| Wolfi rolling | juicefs-1.3 +1 | 1.3.0-r5 | — |
| Wolfi rolling | k8s_gateway | 1.6.1-r0 | — |
| Wolfi rolling | kubernetes-dns-node-cache | 1.26.5-r1 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Go | github.com/coredns/coredns | >= 1.2.0, < 1.12.4 | 1.12.4 | GHSA-93mf-426m-g6x9 |
Advisories 6
- openSUSE-SU-2026:21483-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Jul 31, 2026
- openSUSE-SU-2026:20099-1 Security update for coredns SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2025:15561-1 coredns-1.12.4-2.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- openSUSE-SU-2025:15564-1 govulncheck-vulndb-0.0.20250917T170349-1.1 on GA media SUSE / openSUSE Security Updates · Mar 23, 2026
- SUSE-SU-2025:03289-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2025-2014 CoreDNS: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · Jan 25, 2026