megachangelog
Security2025-12-02

WAF Emergency Release: RCE Generic Framework Rule

Emergency WAF release introducing a new rule to block critical RCE vulnerabilities in web frameworks via unsafe deserialization patterns. The rule blocks malicious POST requests that could allow unauthenticated attackers to execute arbitrary code remotely and compromise systems.

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.
RulesetRule IDLegacy Rule IDDescriptionPrevious ActionNew ActionComments
Cloudflare Managed Ruleset...5fb92fbaN/ARCE Generic - FrameworkN/ABlockThis is a new detection.
Cloudflare Free Ruleset...99702280N/ARCE Generic - FrameworkN/ABlockThis is a new detection.
wafsecurityrceemergencyvulnerability

Source: original entry ↗

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