Cloudflare WAF protections for React2Shell (CVE-2025-55182)
Advisory/Mitigation
Summary
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Cloudflare rolled out WAF protections for CVE-2025-55182 / React2Shell, a mitigation aimed at reducing unauthenticated RCE risk across React deployments. The action came soon after the vulnerability was publicly disclosed on December 3, 2025, as operators rushed to contain exposure. Because React is widely used, the defensive change mattered for a broad internet-facing application base.
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Timeline
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05.12.2025 17:12 2 articles · 7mo ago
Cloudflare rolls out WAF protections for React2Shell
Mitigation Patch UpdateCloudflare rolled out web application firewall (WAF) protections for CVE-2025-55182, also called React2Shell, after the unauthenticated remote code execution flaw in React became public on December 3, 2025. The mitigation was aimed at reducing exposure for Cloudflare customers and internet-facing React deployments.
Show sources
- Cloudflare Outage Caused by React2Shell Mitigations — www.securityweek.com — 05.12.2025 17:12
- Cloudflare Outage Caused by React2Shell Mitigations — www.securityweek.com — 05.12.2025 17:12
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05.12.2025 17:12 1 articles · 7mo ago
Cloudflare investigates outage reports tied to a WAF parsing change
Victim Impact UpdateOn December 5, 2025 at 08:56 UTC, Cloudflare started investigating issues after a change to how its Web Application Firewall parses requests caused its network to be unavailable for several minutes. A fix was rolled out within about half an hour, and outage reports surfaced from Zoom, LinkedIn, Coinbase, DoorDash, and Canva.
Show sources
- Cloudflare Outage Caused by React2Shell Mitigations — www.securityweek.com — 05.12.2025 17:12