Vulnerability in github.com/coredns/coredns (CVE-2026-32934)
Summary
Vulnerability in github.com/coredns/coredns (CVE-2026-32934). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 1.14.3 or later.
Original description
The description as published by the source.
CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the DNS-over-QUIC (DoQ) server can be driven into unbounded goroutine and memory growth by a remote client that opens many QUIC streams and sends only 1 byte per stream. When the worker pool is full, CoreDNS still spawns a goroutine per accepted stream to wait for a worker token. Additionally, active workers block indefinitely in io.ReadFull() with no per-stream read deadline, allowing an attacker to pin all workers by sending a single byte so the read blocks waiting for the second byte of the DoQ length prefix. This enables an unauthenticated remote attacker to cause memory exhaustion and OOM-kill. This issue has been fixed in version 1.14.3. No known workarounds exist.
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A weakness called CVE-2026-32934 was discovered in github.com/coredns/coredns.
Severity is High (CVSS 7.5/10). If exploited, attackers can leak data or disrupt key functionality.
What you should do: update the affected software to the latest version. If unsure, ask your IT team or search the vendor's site for "github.com/coredns/coredns CVE-2026-32934".
CVE-2026-32934 (github.com/coredns/coredns). Severity: High / CVSSv3 7.5. Category: CWE-770.
Response plan:
- Check the vendor advisory for affected versions and the patched release.
- If a vulnerable version is running in production, schedule maintenance (urgency from KEV/CVSS).
- If no patch yet, mitigate via WAF rule, disabling the affected feature, etc.
- Monitor logs / SIEM for known IOC and PoC signatures of this CVE.
PoCs and fix commits: see the 'References' section, MITRE, and NVD.
A weakness (CVE-2026-32934) in github.com/coredns/coredns. A serious software flaw has been identified.
Target versions of github.com/coredns/coredns (see vendor advisory). If running in production, identify exposure immediately.
Severity: High (CVSS 7.5/10). If exploited, attackers can leak data or disrupt key functionality.
Update to the patched release as listed in the vendor advisory. (Typical mitigation pattern for CWE-770)
If a patch is not yet available, consider disabling the affected feature, applying WAF rules, blocking via network ACLs, or isolating the vulnerable version.
Check version information, scan dependencies via SBOM, and monitor SIEM for IOC and PoC signatures related to this CVE.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'github.com/coredns/coredns' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
github.com/coredns/corednsを grep し、稼働しているサービス・バージョンを把握する。 -
6Apply patch patch
Upgrade github.com/coredns/coredns to 1.14.3ステージング環境で 1.14.3 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスと、Step 3 で見つけた異常検知の続報チェックを含めること。
-
7Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番では Step 3 と同じログクエリでアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- web github.com
- web github.com
- web github.com