Emergency WAF managed rule for active RCE vulnerability
Cloudflare released an emergency WAF update with a new managed rule to block exploitation of a critical remote code execution vulnerability in popular web frameworks. The Generic Rules - Remote Code Execution detection prevents attackers from executing arbitrary system commands via malicious input with invalid path sequences.
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.
| Ruleset | Rule ID | Legacy Rule ID | Description | Previous Action | New Action | Comments |
|---|---|---|---|---|---|---|
| Cloudflare Managed Ruleset | ...fd1bf420 | N/A | Generic Rules - Remote Code Execution | N/A | Block | This is a new detection. |
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