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Bug bounty program

CP

Cloudflare Public Bug Bounty

Platform
HackerOne
Bounties
Pays
Assets in scope
51
Disclosed reports
44
Subdomains
24,298
Vendor on CyberSIXT
Cloudflare (70 CVEs, 0 exploited)

Most upvoted reports44

All reports
Most upvoted reports of Cloudflare Public Bug Bounty
ReportWeaknessDisclosedBountyVotes
HTTP Request Smuggling in Transform Rules using hexadecimal escape sequences in the concat() functionAnalysed#1478633Injection and Smuggling2022-05-16$6,000116
Cloudflare CASB Confused Deputy ProblemAnalysed#1952124No weakness recorded2023-06-07$3,30097
Using special IPv4-mapped IPv6 addresses to bypass local IP banAnalysed#1785260No weakness recorded2023-01-24$7,50078
Bypass of Cloudflare's Cache Keys and WAF via header overflow#3027461Access Control2025-11-18–77
Hijack all emails sent to any domain that uses Cloudflare Email ForwardingAnalysed#1419341Access Control2022-07-28$6,00076
`use-mcp`'s oauth2 process uses a window.open call with untrusted mcp server provided data allowing for code execution under the page using itAnalysed#3211031Cross-site Scripting2025-09-30$55075
Yet Another CASB Integration Takeover of Active IntegrationsAnalysed#2094346No weakness recorded2023-11-13–68
[Variation of #3321406] YetAnother 1-Click Chaining of Self-XSS, Cookie Tossing and AntiCSRF Token Prediction leads to auto approval in AccessTempAuthAnalysed#3423950Cross-site Scripting2026-04-14–63
AI Playground XSS to steal user-chat messages and access to connected MCP ServerAnalysed#3424998Cross-site Scripting2026-02-26–62
Bypass R2 payment screenAnalysed#2170559Authentication2023-11-10$35057

Subdomains24,298

Subdomains of Cloudflare Public Bug Bounty
NameScopeFirst seen
cf-190-93-255-149.cloudflare.comIn scope2026-11-14
cf-190-93-255-15.cloudflare.comIn scope2026-11-14
cf-190-93-255-150.cloudflare.comIn scope2026-11-14
cf-190-93-255-151.cloudflare.comIn scope2026-11-14
cf-190-93-255-152.cloudflare.comIn scope2026-11-14
cf-190-93-255-153.cloudflare.comIn scope2026-11-14
cf-190-93-255-154.cloudflare.comIn scope2026-11-14
cf-190-93-255-155.cloudflare.comIn scope2026-11-14
cf-190-93-255-156.cloudflare.comIn scope2026-11-14
cf-190-93-255-157.cloudflare.comIn scope2026-11-14
cf-190-93-255-158.cloudflare.comIn scope2026-11-14
cf-190-93-255-159.cloudflare.comIn scope2026-11-14
cf-190-93-255-16.cloudflare.comIn scope2026-11-14
cf-190-93-255-160.cloudflare.comIn scope2026-11-14
cf-190-93-255-161.cloudflare.comIn scope2026-11-14
cf-190-93-255-162.cloudflare.comIn scope2026-11-14
cf-190-93-255-163.cloudflare.comIn scope2026-11-14
cf-190-93-255-164.cloudflare.comIn scope2026-11-14
cf-190-93-255-165.cloudflare.comIn scope2026-11-14
cf-190-93-255-166.cloudflare.comIn scope2026-11-14
cf-190-93-255-167.cloudflare.comIn scope2026-11-14
cf-190-93-255-168.cloudflare.comIn scope2026-11-14
cf-190-93-255-169.cloudflare.comIn scope2026-11-14
cf-190-93-255-17.cloudflare.comIn scope2026-11-14
cf-190-93-255-170.cloudflare.comIn scope2026-11-14
cf-190-93-255-171.cloudflare.comIn scope2026-11-14
cf-190-93-255-172.cloudflare.comIn scope2026-11-14
cf-190-93-255-173.cloudflare.comIn scope2026-11-14
cf-190-93-255-174.cloudflare.comIn scope2026-11-14
cf-190-93-255-175.cloudflare.comIn scope2026-11-14
cf-190-93-255-176.cloudflare.comIn scope2026-11-14
cf-190-93-255-177.cloudflare.comIn scope2026-11-14
cf-190-93-255-178.cloudflare.comIn scope2026-11-14
cf-190-93-255-179.cloudflare.comIn scope2026-11-14
cf-190-93-255-18.cloudflare.comIn scope2026-11-14
cf-190-93-255-180.cloudflare.comIn scope2026-11-14
cf-190-93-255-181.cloudflare.comIn scope2026-11-14
cf-190-93-255-182.cloudflare.comIn scope2026-11-14
cf-190-93-255-183.cloudflare.comIn scope2026-11-14
cf-190-93-255-184.cloudflare.comIn scope2026-11-14
cf-190-93-255-185.cloudflare.comIn scope2026-11-14
cf-190-93-255-186.cloudflare.comIn scope2026-11-14
cf-190-93-255-187.cloudflare.comIn scope2026-11-14
cf-190-93-255-188.cloudflare.comIn scope2026-11-14
cf-190-93-255-189.cloudflare.comIn scope2026-11-14
cf-190-93-255-19.cloudflare.comIn scope2026-11-14
cf-190-93-255-190.cloudflare.comIn scope2026-11-14
cf-190-93-255-191.cloudflare.comIn scope2026-11-14
cf-190-93-255-192.cloudflare.comIn scope2026-11-14
cf-190-93-255-193.cloudflare.comIn scope2026-11-14
cf-190-93-255-194.cloudflare.comIn scope2026-11-14
cf-190-93-255-195.cloudflare.comIn scope2026-11-14
cf-190-93-255-196.cloudflare.comIn scope2026-11-14
cf-190-93-255-197.cloudflare.comIn scope2026-11-14
cf-190-93-255-198.cloudflare.comIn scope2026-11-14
cf-190-93-255-199.cloudflare.comIn scope2026-11-14
cf-190-93-255-20.cloudflare.comIn scope2026-11-14
cf-190-93-255-200.cloudflare.comIn scope2026-11-14
cf-190-93-255-201.cloudflare.comIn scope2026-11-14
cf-190-93-255-202.cloudflare.comIn scope2026-11-14
cf-190-93-255-203.cloudflare.comIn scope2026-11-14
cf-190-93-255-204.cloudflare.comIn scope2026-11-14
cf-190-93-255-205.cloudflare.comIn scope2026-11-14
cf-190-93-255-206.cloudflare.comIn scope2026-11-14
cf-190-93-255-207.cloudflare.comIn scope2026-11-14
cf-190-93-255-208.cloudflare.comIn scope2026-11-14
cf-190-93-255-209.cloudflare.comIn scope2026-11-14
cf-190-93-255-21.cloudflare.comIn scope2026-11-14
cf-190-93-255-210.cloudflare.comIn scope2026-11-14
cf-190-93-255-211.cloudflare.comIn scope2026-11-14
cf-190-93-255-212.cloudflare.comIn scope2026-11-14
cf-190-93-255-213.cloudflare.comIn scope2026-11-14
cf-190-93-255-214.cloudflare.comIn scope2026-11-14
cf-190-93-255-215.cloudflare.comIn scope2026-11-14
cf-190-93-255-216.cloudflare.comIn scope2026-11-14
cf-190-93-255-217.cloudflare.comIn scope2026-11-14
cf-190-93-255-218.cloudflare.comIn scope2026-11-14
cf-190-93-255-219.cloudflare.comIn scope2026-11-14
cf-190-93-255-22.cloudflare.comIn scope2026-11-14
cf-190-93-255-220.cloudflare.comIn scope2026-11-14
cf-190-93-255-221.cloudflare.comIn scope2026-11-14
cf-190-93-255-222.cloudflare.comIn scope2026-11-14
cf-190-93-255-223.cloudflare.comIn scope2026-11-14
cf-190-93-255-224.cloudflare.comIn scope2026-11-14
cf-190-93-255-225.cloudflare.comIn scope2026-11-14
cf-190-93-255-226.cloudflare.comIn scope2026-11-14
cf-190-93-255-227.cloudflare.comIn scope2026-11-14
cf-190-93-255-228.cloudflare.comIn scope2026-11-14
cf-190-93-255-229.cloudflare.comIn scope2026-11-14
cf-190-93-255-23.cloudflare.comIn scope2026-11-14
cf-190-93-255-230.cloudflare.comIn scope2026-11-14
cf-190-93-255-231.cloudflare.comIn scope2026-11-14
cf-190-93-255-232.cloudflare.comIn scope2026-11-14
cf-190-93-255-233.cloudflare.comIn scope2026-11-14
cf-190-93-255-234.cloudflare.comIn scope2026-11-14
cf-190-93-255-235.cloudflare.comIn scope2026-11-14
cf-190-93-255-236.cloudflare.comIn scope2026-11-14
cf-190-93-255-237.cloudflare.comIn scope2026-11-14
cf-190-93-255-238.cloudflare.comIn scope2026-11-14
cf-190-93-255-239.cloudflare.comIn scope2026-11-14

18,935 names are covered by the program's own scope; 2 were first seen this week. Names come from ProjectDiscovery's public Chaos dataset (passive sources: certificate logs, DNS and other public data), matched to the program by its listing and its own domain scope. A name being in a dataset is not permission to test it: only what the program's own scope says is in scope, and its policy decides. CyberSIXT does not resolve, probe or scan these names. Tags come from the name alone. Source: ProjectDiscovery Chaos. Subdomains on the Atlas, or search the subdomains of every program.

A name in a dataset is not permission to test it: the program's own scope and rules decide. Data as of 2026-11-15.