Changelog

Cloudflare Rulesets now include new functions that enable advanced expression logic for evaluating arrays and maps. These functions allow you to build rules that match against lists of values in request or response headers, enabling use cases like country-based blocking using custom headers.

Check if a country code exists in a header list:

has_value(split(http.response.headers["x-allow-country"][0], ","), ip.src.country)

Check if a specific header key exists:

has_key(http.request.headers, "x-custom-header")

Join array values for logging or comparison:

join(http.request.headers.names, ", ")

For more information, refer to the Functions reference.

This week's release focuses on improvements to existing detections to enhance coverage.

Key Findings

• Existing rule enhancements have been deployed to improve detection resilience against SQL injection.

We have made it easier to validate connectivity when deploying WARP Connector as part of your software-defined private network.

You can now ping the WARP Connector host directly on its LAN IP address immediately after installation. This provides a fast, familiar way to confirm that the Connector is online and reachable within your network before testing access to downstream services.

Starting with version 2025.10.186.0, WARP Connector responds to traffic addressed to its own LAN IP, giving you immediate visibility into Connector reachability.

Learn more about deploying WARP Connector and building private network connectivity with Cloudflare One.

This week's release focuses on improvements to existing detections to enhance coverage.

Key Findings

• Existing rule enhancements have been deployed to improve detection resilience against SQL Injection.

We have expanded the reporting capabilities of the Cloudflare URL Scanner. In addition to existing JSON and HAR exports, users can now generate and download a PDF report directly from the Cloudflare dashboard. This update streamlines how security analysts can share findings with stakeholders who may not have access to the Cloudflare dashboard or specialized tools to parse JSON and HAR files.

Key Benefits:

• Consolidate scan results, including screenshots, security signatures, and metadata, into a single, portable document
• Easily share professional-grade summaries with non-technical stakeholders or legal teams for faster incident response

What’s new:

• PDF Export Button: A new download option is available in the URL Scanner results page within the Cloudflare dashboard
• Unified Documentation: Access all scan details—from high-level summaries to specific security flags—in one offline-friendly file

To get started with the URL Scanner and explore our reporting capabilities, visit the URL Scanner API documentation ↗.

The ip.src.metro_code field in the Ruleset Engine is now populated with DMA (Designated Market Area) data.

You can use this field to build rules that target traffic based on geographic market areas, enabling more granular location-based policies for your applications.

Example filter expression:

ip.src.metro_code eq "501"

For more information, refer to the Fields reference.

We are excited to announce that Cloudflare Threat Events now supports the STIX2 (Structured Threat Information Expression) format. This was a highly requested feature designed to streamline how security teams consume and act upon our threat intelligence.

By adopting this industry-standard format, you can now integrate Cloudflare's threat events data more effectively into your existing security ecosystem.

• Eliminate the need for custom parsers, as STIX2 allows for "out of the box" ingestion into major Threat Intel Platforms (TIPs), SIEMs, and SOAR tools.

• STIX2 provides a standardized way to represent relationships between indicators, sightings, and threat actors, giving your analysts a clearer picture of the threat landscape.

For technical details on how to query events using this format, please refer to our Threat Events API Documentation ↗.

This week's release focuses on improvements to existing detections to enhance coverage.

Key Findings

• Existing rule enhancements have been deployed to improve detection resilience against SQL Injection.

This week's release focuses on improvements to existing detections to enhance coverage.

Key Findings

• Existing rule enhancements have been deployed to improve detection resilience against broad classes of web attacks and strengthen behavioral coverage.

This emergency release introduces rules for CVE-2025-55183 and CVE-2025-55184, targeting server-side function exposure and resource-exhaustion patterns, respectively.

Key Findings

Added coverage for Leaking Server Functions (CVE-2025-55183) and React Function DoS detection (CVE-2025-55184).

Impact

These updates strengthen protection for server-function abuse techniques (CVE-2025-55183, CVE-2025-55184) that may expose internal logic or disrupt application availability.

This additional week's emergency release introduces improvements to our existing rule for React – Remote Code Execution – CVE-2025-55182 - 2, along with two new generic detections covering server-side function exposure and resource-exhaustion patterns.

Key Findings

Enhanced detection logic for React – RCE – CVE-2025-55182, added Generic – Server Function Source Code Exposure, and added Generic – Server Function Resource Exhaustion.

Impact

These updates strengthen protection against React RCE exploitation attempts and broaden coverage for common server-function abuse techniques that may expose internal logic or disrupt application availability.

Cloudflare WAF now inspects request-payload size of up to 1 MB across all plans to enhance our detection capabilities for React RCE (CVE-2025-55182).

Key Findings

React payloads commonly have a default maximum size of 1 MB. Cloudflare WAF previously inspected up to 128 KB on Enterprise plans, with even lower limits on other plans.

Update: We later reinstated the maximum request-payload size the Cloudflare WAF inspects. Refer to Updating the WAF maximum payload values for details.

We are reinstating the maximum request-payload size the Cloudflare WAF inspects, with WAF on Enterprise zones inspecting up to 128 KB.

Key Findings

On December 5, 2025, we initially attempted to increase the maximum WAF payload limit to 1 MB across all plans. However, an automatic rollout for all customers proved impractical because the increase led to a surge in false positives for existing managed rules.

This issue was particularly notable within the Cloudflare Managed Ruleset and the Cloudflare OWASP Core Ruleset, impacting customer traffic.

Impact

Customers on paid plans can increase the limit to 1 MB for any of their zones by contacting Cloudflare Support. Free zones are already protected up to 1 MB and do not require any action.

The WAF rule deployed yesterday to block unsafe deserialization-based RCE has been updated. The rule description now reads “React – RCE – CVE-2025-55182”, explicitly mapping to the recently disclosed React Server Components vulnerability. Detection logic remains unchanged.

Key Findings

Rule description updated to reference React – RCE – CVE-2025-55182 while retaining existing unsafe-deserialization detection.

Impact

Improved classification and traceability with no change to coverage against remote code execution attempts.

This week's emergency release introduces a new rule to block a critical RCE vulnerability in widely-used web frameworks through unsafe deserialization patterns.

Key Findings

New WAF rule deployed for RCE Generic Framework to block malicious POST requests containing unsafe deserialization patterns. If successfully exploited, this vulnerability allows attackers with network access via HTTP to execute arbitrary code remotely.

Impact

• Successful exploitation allows unauthenticated attackers to execute arbitrary code remotely through crafted serialization payloads, enabling complete system compromise, data exfiltration, and potential lateral movement within affected environments.

This week’s release introduces new detections for remote code execution attempts targeting Monsta FTP (CVE-2025-34299), alongside improvements to an existing XSS detection to enhance coverage.

Key Findings

• CVE-2025-34299 is a critical remote code execution flaw in Monsta FTP, arising from improper handling of user-supplied parameters within the file-handling interface. Certain builds allow crafted requests to bypass sanitization and reach backend PHP functions that execute arbitrary commands. Attackers can send manipulated parameters through the web panel to trigger command execution within the application’s runtime environment.

Impact

If exploited, the vulnerability enables full remote command execution on the underlying server, allowing takeover of the hosting environment, unauthorized file access, and potential lateral movement. As the flaw can be triggered without authentication on exposed Monsta FTP instances, it represents a severe risk for publicly reachable deployments.

API Shield now automatically detects zombie endpoints — saved endpoints that have not received traffic for an extended period. When detected, the cf-risk-zombie risk label is applied.

The scan runs daily alongside existing risk scans. Endpoints are labeled after 32 days without traffic.

Zombie endpoints may indicate deprecated or forgotten API surface area that could pose a security risk. Review these endpoints and consider removing them from Endpoint Management if they are no longer in use. Also consider using a fallthrough rule to prevent communication with endpoints removed from Endpoint Management.

This week highlights enhancements to detection signatures improving coverage for vulnerabilities in FortiWeb, linked to CVE-2025-64446, alongside new detection logic expanding protection against PHP Wrapper Injection techniques.

Key Findings

This vulnerability enables an unauthenticated attacker to bypass access controls by abusing the CGIINFO header. The latest update strengthens detection logic to ensure a reliable identification of crafted requests attempting to exploit this flaw.

Impact

• FortiWeb (CVE-2025-64446): Exploitation allows a remote unauthenticated adversary to circumvent authentication mechanisms by sending a manipulated CGIINFO header to FortiWeb’s backend CGI handler. Successful exploitation grants unintended access to restricted administrative functionality, potentially enabling configuration tampering or system-level actions.

The threat events platform now has threat insights available for some relevant parent events. Threat intelligence analyst users can access these insights for their threat hunting activity. Insights are also highlighted in the Cloudflare dashboard by a small lightning icon and the insights can refer to multiple, connected events, potentially part of the same attack or campaign and associated with the same threat actor.

For more information, refer to Analyze threat events.

This week’s release introduces a critical detection for CVE-2025-61757, a vulnerability in the Oracle Identity Manager REST WebServices component.

Key Findings

This flaw allows unauthenticated attackers with network access over HTTP to fully compromise the Identity Manager, potentially leading to a complete takeover.

Impact

Oracle Identity Manager (CVE-2025-61757): Exploitation could allow an unauthenticated remote attacker to bypass security checks by sending specially crafted requests to the application's message processor. This enables the creation of arbitrary employee accounts, which can be leveraged to modify system configurations and achieve full system compromise.

This week highlights enhancements to detection signatures improving coverage for vulnerabilities in DELMIA Apriso, linked to CVE-2025-6205.

Key Findings

This vulnerability allows unauthenticated attackers to gain privileged access to the application. The latest update provides enhanced detection logic for resilient protection against exploitation attempts.

Impact

• DELMIA Apriso (CVE-2025-6205): Exploitation could allow an unauthenticated remote attacker to bypass security checks by sending specially crafted requests to the application's message processor. This enables the creation of arbitrary employee accounts, which can be leveraged to modify system configurations and achieve full system compromise.

Now, API Shield automatically searches for and highlights Broken Object Level Authorization (BOLA) attacks on managed API endpoints. API Shield will highlight both BOLA enumeration attacks and BOLA pollution attacks, telling you what was attacked, by who, and for how long.

You can find these attacks three different ways: Security Overview, Endpoint details, or Security Analytics. If these attacks are not found on your managed API endpoints, there will not be an overview card or security analytics suspicious activity card.

On the Security Overview card, select the suggestion > View details to review the top attacked API endpoints, endpoint details, and the attack summary:

From the endpoint details, you can select View attack to find details about the BOLA attacker’s sessions.

From here, select View in Analytics to observe attacker traffic over time for the last seven days.

Your search will filter to traffic on that endpoint in the last seven days, along with the malicious session IDs found in the attack. Session IDs are hashed for privacy and will not be found in your origin logs. Refer to IP and JA4 fingerprint to cross-reference behavior at the origin.

At any time, you can also start your investigation into attack traffic from Security Analytics by selecting the suspicious activity card.

We urge you to take all of this client information to your developer team to research the attacker behavior and ensure any broken authorization policies in your API are fixed at the source in your application, preventing further abuse.

In addition, this release marks the end of the beta period for these scans. All Enterprise customers with API Shield subscriptions will see these new attacks if found on their zone.

Starting February 2, 2026, the cloudflared proxy-dns command will be removed from all new cloudflared releases.

This change is being made to enhance security and address a potential vulnerability in an underlying DNS library. This vulnerability is specific to the proxy-dns command and does not affect any other cloudflared features, such as the core Cloudflare Tunnel service.

The proxy-dns command, which runs a client-side DNS-over-HTTPS (DoH) proxy, has been an officially undocumented feature for several years. This functionality is fully and securely supported by our actively developed products.

Versions of cloudflared released before this date will not be affected and will continue to operate. However, note that our official support policy for any cloudflared release is one year from its release date.

We strongly advise users of this undocumented feature to migrate to one of the following officially supported solutions before February 2, 2026, to continue benefiting from secure DNS-over-HTTPS.

The preferred method for enabling DNS-over-HTTPS on user devices is the Cloudflare WARP client. The WARP client automatically secures and proxies all DNS traffic from your device, integrating it with your organization's Zero Trust policies and posture checks.

For scenarios where installing a client on every device is not possible (such as servers, routers, or IoT devices), we recommend using the WARP Connector.

Instead of running cloudflared proxy-dns on a machine, you can install the WARP Connector on a single Linux host within your private network. This connector will act as a gateway, securely routing all DNS and network traffic from your entire subnet to Cloudflare for filtering and logging.

This week’s release introduces new detections for Prototype Pollution across three common vectors: URI, Body, and Header/Form.

Key Findings

• These attacks can affect both API and web applications by altering normal behavior or bypassing security controls.

Impact

Exploitation may allow attackers to change internal logic or cause unexpected behavior in applications using JavaScript or Node.js frameworks. Developers should sanitize input keys and avoid merging untrusted data structures.

This week’s emergency release introduces a new detection signature that enhances coverage for a critical vulnerability in the React Native Metro Development Server, tracked as CVE-2025-11953.

Key Findings

The Metro Development Server exposes an HTTP endpoint that is vulnerable to OS command injection (CWE-78). An unauthenticated network attacker can send a crafted request to this endpoint and execute arbitrary commands on the host running Metro. The vulnerability affects Metro/cli-server-api builds used by React Native Community CLI in pre-patch development releases.

Impact

Successful exploitation of CVE-2025-11953 may result in remote command execution on developer workstations or CI/build agents, leading to credential and secret exposure, source tampering, and potential lateral movement into internal networks. Administrators and developers are strongly advised to apply the vendor's patches and restrict Metro’s network exposure to reduce this risk.