# CVE-2026-33489: CoreDNS transfer plugin subzone ACL bypass via lexicographic zone comparison > Remote attackers can bypass subzone access controls to retrieve full zone data via AXFR/IXFR due to incorrect ACL matching logic in CoreDNS. - **Severity:** High 8.2 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 5 May 2026 - **Updated:** 5 May 2026 - **Also known as:** AZL-85721, CLEANSTART-2026-GQ96342, CLEANSTART-2026-XP67395, ECHO-de9e-afd3-21e9, GHSA-h8mm-c463-wjq3, GO-2026-5417, MINI-28pp-457w-24vp, MINI-3q3v-m4w2-9vc3, MINI-452f-wh2g-x2jh, MINI-47v7-6h3w-j3cx, MINI-4gjp-8qx6-9pr6, MINI-4x79-qc8w-8xf6, MINI-58cg-q5gw-v7g8, MINI-5xp3-xjp4-6qx2, MINI-75gr-j7j2-cjjj, MINI-7xj9-78h9-qxq3, MINI-c34v-47gg-wf36, MINI-hvmm-5xpg-p6q3, MINI-j5m4-hf4m-mfx6, MINI-jc5p-5v23-gqhh, MINI-m4w6-4fhm-rrvx, MINI-qrc8-5mvw-w7vh, MINI-qw4v-4856-9ww5, MINI-v8v2-4hvj-jvfc, MINI-xp97-f28g-34rj, MINI-xx2w-m392-65pq ## What is CVE-2026-33489? CVE-2026-33489 is a high-severity missing authorization vulnerability in coredns, published on 5 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description CoreDNS is a DNS server that chains plugins. In versions prior to 1.14.3, the transfer plugin can select the wrong ACL stanza when both a parent zone and a more-specific subzone are configured. The longestMatch() function in plugin/transfer/transfer.go uses a lexicographic string comparison instead of an actual longest-suffix match to select the winning zone. As a result, a permissive parent-zone transfer rule can override a restrictive subzone rule depending on zone name ordering (e.g., "example.org." > "a.example.org." lexicographically). This allows an unauthorized remote client to perform AXFR/IXFR for the subzone and retrieve its full zone contents. This issue has been fixed in version 1.14.3. Weakness: CWE-863 (Incorrect Authorization) ## Which versions are affected by CVE-2026-33489? 3 open source packages ship an affected version, including github.com/coredns/coredns. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/coredns/coredns` | Go | All versions | 1.14.3 | | `github.com/coredns/coredns` | Go | All versions | 1.14.3 | | `github.com/coredns/coredns` | Go | All versions | 1.14.3 | Products: Coredns.io Coredns. ## How do I fix CVE-2026-33489? Upgrade github.com/coredns/coredns to 1.14.3 or later. ## Is CVE-2026-33489 being exploited? It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33489 exists. ## Other vulnerabilities in coredns - [CVE-2026-32934](https://insights.sbomify.com/CVE-2026-32934/): CoreDNS DNS-over-QUIC unbounded goroutine growth leads to denial of service (high 8.7) - [CVE-2026-32936](https://insights.sbomify.com/CVE-2026-32936/): CoreDNS DoH GET path missing size validation causes CPU and memory amplification (high 8.7) - [CVE-2026-33190](https://insights.sbomify.com/CVE-2026-33190/): CoreDNS TSIG authentication bypass on encrypted DNS transports (high 8.7) - [CVE-2026-35579](https://insights.sbomify.com/CVE-2026-35579/): CoreDNS TSIG authentication bypass on gRPC, QUIC, DoH, and DoH3 transports (high 8.2) - [CVE-2026-26017](https://insights.sbomify.com/CVE-2026-26017/): CoreDNS ACL Bypass (high 7.7) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-33489 and fix it if it is affected. What it is: CVE-2026-33489 is a high-severity missing authorization vulnerability in coredns, published on 5 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-33489 exists. Affected packages and fixed versions: - github.com/coredns/coredns (Go): affected all versions; fixed in 1.14.3 - github.com/coredns/coredns (Go): affected all versions; fixed in 1.14.3 - github.com/coredns/coredns (Go): affected all versions; fixed in 1.14.3 Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-33489/ (Markdown: https://insights.sbomify.com/CVE-2026-33489/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33489 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33489 - OSV: https://osv.dev/vulnerability/CVE-2026-33489 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-33489/ Summaries are generated and may contain mistakes; the official description above is the record.