Changelog

This emergency release will add two rules related to the Brotli vulnerability CVE-2026-111497 to the Cloudflare Managed Ruleset. Both rules will be enabled by default with their action set to Log, providing visibility into matching requests so customers can evaluate the impact before choosing to block them.

Rule behavior

• Brotli rule: Matches incoming requests that declare Brotli request-body encoding (Content-Encoding: br), including legitimate clients submitting Brotli-encoded request bodies. It does not match Accept-Encoding: br or affect Cloudflare's Brotli response-compression settings. The rule's default action is Log.
• Next.js rule: Matches requests to the Next.js image optimization endpoint (/_next/image), including legitimate image optimization traffic. The default action is Log and does not block requests. Changing the action to Block may prevent optimized images from loading and disrupt image delivery for applications using this endpoint.

Default behavior

• Both rules will log matching requests without blocking them when the ruleset defaults are used.
• Customers will be able to review matches in analytics and configure a blocking action for either rule if desired.
• Enabling these rules in Log mode provides visibility only; it does not block requests matching these rules.

Important: Check existing action overrides

If you have configured a ruleset-level action override that applies Block to these rules, matching requests may be blocked as soon as the rules are deployed, despite their default Log action. This may result in false positives and block legitimate traffic.

Review your existing ruleset overrides before deployment. If you want to evaluate these rules without blocking traffic, configure rule-specific overrides to use Log and review matching requests before switching to Block.

This emergency release updates the names and metadata of seven existing rules in the Cloudflare Managed Ruleset to identify CVE-2026-109618 and CVE-2026-109619. Detection logic and rule actions remain unchanged.

For more information, refer to WAF Managed Rules.

This emergency release updates the names and metadata of seven existing rules in the Cloudflare Free Ruleset to identify CVE-2026-109618 and CVE-2026-109619. Detection logic and rule actions remain unchanged.

For more information, refer to WAF Managed Rules.

This emergency release adds seven rules to the Cloudflare Managed Ruleset to detect anomalous request patterns.

For more information, refer to WAF Managed Rules.

This emergency release adds seven rules to the Cloudflare Free Ruleset to block anomalous request patterns.

For more information, refer to WAF Managed Rules.

This emergency release adds a new managed rule to block active exploitation of a critical remote code execution (RCE) vulnerability found in popular web frameworks.

Key Findings

Key Findings

• Generic Rules - Remote Code Execution: Attackers can execute arbitrary system commands with web server privileges by sending malicious input containing invalid path sequences during request processing.

This release introduces new detections to mitigate recent vulnerabilities affecting TanStack and Atlassian products.

Key Findings

• CVE-2026-102989: A reflected Cross-Site Scripting (XSS) vulnerability affecting TanStack. Unauthenticated attackers can exploit this flaw to inject malicious scripts into web pages viewed by other users, potentially leading to session hijacking or unauthorized actions.

• CVE-2026-21589: An arbitrary file access vulnerability affecting Atlassian products. Threat actors can exploit this flaw to read unauthorized files on the target system, risking the exposure of sensitive configuration data.

You can now use cf.appsec.request.failed_detections to control how your rules handle requests when a security detection reports a failure.

The field is an Array<String> of detection IDs that reports failures from content scanning, WAF attack score, attack signature detection, leaked credentials detection, and AI prompt detections for personally identifiable information (PII), prompt injection, custom topics, and unsafe topics.

The field does not alter the existing behavior of detections. Use it in rules to choose how to handle requests with reported failures.

When no failures are reported, the field returns []. You can use it on all plans, but your plan must still include the detections and rule features you want to use.

Supported rules:

• Custom rules at the zone and account levels
• Rate limiting rules at the zone and account levels
• Request Header Transform Rules at the zone level

Match any reported failure:

len(cf.appsec.request.failed_detections) gt 0

Match a reported leaked credentials detection failure:

any(cf.appsec.request.failed_detections[*] eq "waf_credential_check")

For more information, refer to the Failed detections field reference.

AI Security for Apps now supports an updated set of categories for detecting unsafe topics in incoming prompts.

The values available in cf.llm.prompt.unsafe_topic_categories have changed. Existing WAF custom rules remain valid, but rules that reference a removed or renamed category will no longer match that category. Review any rules that use this field and update their expressions to use the currently supported values.

For category descriptions and configuration guidance, refer to Unsafe topics.

This release introduces a new detection to mitigate a heap-based buffer overflow vulnerability in F5 BIG-IP, and enhances existing command injection protections by incorporating tested beta logic into the baseline rule.

Key Findings

• CVE-2026-94127: A heap-based buffer overflow vulnerability in F5 BIG-IP. Attackers can exploit this flaw to execute arbitrary code on the affected system.

This update provides immediate defense against a vulnerability affecting Citrix NetScaler ADC and Gateway appliances, deploying protection against improper input validation vectors.

Key Findings

• CVE-2026-88771: An improper input validation vulnerability affecting Citrix NetScaler ADC and Gateway allows an unauthenticated attacker to execute arbitrary commands.

Impact

We strongly recommend that administrators apply the latest versions to fully secure origin servers. Additionally, customers should review configurations against applicable preconditions and follow standard incident response processes if signs of compromise are identified.

Detailed Rule Changes

This release introduces new detections to enhance protection against a specific GitLab path traversal vulnerability, alongside advanced generic rules targeting HTTP request smuggling, directory traversal, and command injection attempts.

Key Findings

• CVE-2026-85706: A path traversal vulnerability affecting GitLab.

This update provides immediate defense against critical vulnerabilities affecting WordPress and JFrog Artifactory, including path traversal, local file inclusion (LFI), cross-site scripting (XSS), and authentication bypass exploits.

Key Findings

• CVE-2026-87902: A high-severity Path Traversal and Local File Inclusion (LFI) vulnerability affecting WordPress. Unauthenticated attackers can exploit this flaw to read arbitrary files on the host server, potentially exposing sensitive configuration data or system files.

• CVE-2026-42018 & CVE-2026-82329: Critical authentication bypass vulnerabilities affecting JFrog Artifactory. Successful exploitation allows unauthenticated attackers to bypass security controls and achieve unauthorized access to the Artifactory instance.

Impact

We strongly recommend that administrators apply the latest vendor patches for WordPress and JFrog Artifactory to fully secure origin servers.

Detailed Rule Changes

This release introduces new threat detections to enhance protection against Server-Side Request Forgery (SSRF) attempts using non-standard IP notations or jar loopback payloads, alongside new defenses against Server-Side Template Injection (SSTI) targeting Jinja environments.

This release introduces new threat detections to enhance protection against command injection attempts, Server-Side Request Forgery (SSRF) targeting cloud metadata, and information disclosure within version control history.

This update provides immediate defense against a high-severity, actively exploited zero-day vulnerability targeting Adobe Commerce and Magento Open Source storefronts.

Key Findings

• Adobe Commerce and Magento RCE (CVE-2026-75650 / "StyleSmuggler"): Unauthenticated Remote Code Execution (RCE) vulnerability caused by improper neutralization of special elements in the platform's template engine. Unauthenticated attackers can inject arbitrary PHP payloads through style properties to execute system commands and deploy persistent malware.

Impact

This emergency rule provides immediate edge-level mitigation and virtual patching, origin applications must be urgently updated. We strongly recommend to apply the hotfix outlined in Adobe Security Bulletin APSB26-146 and immediately rotate all potentially exposed encryption keys, integration tokens, and system credentials, as patching alone does not remediate an existing compromise.

This release enhances detection logic for existing rules targeting Next.js remote code execution (RCE) vulnerabilities by consolidating active beta rules into baseline signatures.

Application Profiles add a positive-security layer to Cloudflare WAF. Instead of looking only for requests that resemble known attacks, Application Profiles learn what valid requests to your application look like and identify traffic that deviates from the expected structure.

The first available profile type, Schema Profiles, can learn path variables, query parameters, headers, cookies, JSON bodies, and form-encoded bodies. Profiles model field types and constraints such as numeric ranges, string lengths, and character classes. After a profile becomes available, an always-on detection classifies requests as conforming or non-conforming without blocking traffic.

Use Profile Analysis in Security Analytics to review conformance trends and sampled violation details before enforcing a profile. When you are ready to mitigate traffic, use a Custom Rule to scope enforcement by hostname, path, operation, or other security signals such as Attack Score.

Customers with API Security already have access to Schema Profiles through Schema Learning and Schema Validation. Cloudflare is also opening a closed beta to invited Enterprise customers without API Security. Contact your Cloudflare account team to express interest.

For more information, refer to Application Profiles.

Attack Signature Detection is now available in Early Access. It evaluates requests against Cloudflare attack signatures and records matches without applying a mitigation action, allowing you to investigate detected traffic before deciding how to respond.

In Security Analytics > Attack Analysis, you can review matching signature references, categories, confidence levels, and request outcomes. You can then use these fields in Security Rules and combine them with request properties such as hostname, path, and HTTP method to apply scoped mitigation.

Attack Signature Detection uses the same signature definitions as Cloudflare Managed Rules, but it does not inherit your Managed Rules actions, overrides, or deployment configuration. Managed Rules remain the recommended baseline protection during Early Access.

Contact your Cloudflare account team to request access. For more information, refer to Attack Signature Detection.

AI Security for Apps now supports an updated set of categories for detecting personally identifiable information (PII) in incoming prompts.

The values available in cf.llm.prompt.pii_categories have changed. Existing WAF custom rules remain valid, but rules that reference a removed or renamed category will no longer match that category. Review any rules that use this field and update their expressions to use the currently supported values.

For the complete category list and configuration guidance, refer to PII detection.

This release introduces a new threat detection to enhance protection against SQL injection (SQLi) attempts exploiting complex query syntax.

Key Findings

• SQLi Protection: Improved coverage for SQL injection patterns involving WHERE comparisons combined with WITH clauses.

This emergency release updates an existing Next.js remote code execution rule to identify CVE-2026-75604 and adds a new rule for remote code execution in the Next.js Image Optimizer via crafted AVIF images.

Key Findings

• CVE-2026-75604 affects Windows-hosted Next.js applications using both the Pages Router and App Router without Cache Components and can lead to unauthenticated remote code execution.

• GHSA-2xp9-vwfh-vxw4 affects the Next.js Image Optimizer and can lead to unauthenticated remote code execution when it optimizes an attacker-controlled AVIF image.

Impact

Next.js recommends updating to version 16.3.3 or 15.5.24 to address these vulnerabilities.

This release moves four new detections from Log to Block, merges the XSS, HTML Injection - Script Tag - Beta rule into the original rule, and adds a Generic Rules - Remote Code Execution rule in Block mode.

Key Findings

• Four new detections move from Log to Block: HTTP/2 Request Smuggling - Request Body Anomaly and XSS - JavaScript Event Handler Coercion across Headers, Body, and URI.

• The XSS, HTML Injection - Script Tag - Beta rule is merged into the original rule.

• A Generic Rules - Remote Code Execution detection is added in Block mode.

Leaked credentials detection now scans the Authorization request header for Basic Authentication credentials. Previously, the detection only inspected request bodies, query strings, and headers for well-known web applications or custom detection locations, which meant credentials sent through HTTP Basic Authentication were not covered by default.

This new default scan location decodes the Authorization: Basic <credentials> header and compares the extracted username and password against Cloudflare's database of leaked credentials, the same way as other default scan locations. Matches populate the existing leaked credentials fields, such as cf.waf.credential_check.password_leaked, and trigger the Exposed-Credential-Check managed transform header if configured, so you can reuse existing custom rules and rate limiting rules without changes.

This change was applied automatically for zones with leaked credentials detection enabled. No configuration changes are required.

For more information, refer to Leaked credentials detection.

This release updates WordPress remote code execution rule metadata in the Cloudflare Managed Ruleset and Cloudflare Free Ruleset to identify CVE-2026-65640.

Key Findings

• CVE-2026-65640: A remote code execution vulnerability affecting WordPress core and plugin components. Remote, unauthenticated attackers can execute arbitrary system commands to gain unauthorized access or establish backdoors on host servers.

Impact

The WordPress changes update rule metadata only; detection behavior and actions remain unchanged.