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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-190-93-248-200.cloudflare.comIn scope2026-11-14
cf-190-93-248-201.cloudflare.comIn scope2026-11-14
cf-190-93-248-202.cloudflare.comIn scope2026-11-14
cf-190-93-248-203.cloudflare.comIn scope2026-11-14
cf-190-93-248-204.cloudflare.comIn scope2026-11-14
cf-190-93-248-205.cloudflare.comIn scope2026-11-14
cf-190-93-248-206.cloudflare.comIn scope2026-11-14
cf-190-93-248-207.cloudflare.comIn scope2026-11-14
cf-190-93-248-208.cloudflare.comIn scope2026-11-14
cf-190-93-248-209.cloudflare.comIn scope2026-11-14
cf-190-93-248-21.cloudflare.comIn scope2026-11-14
cf-190-93-248-210.cloudflare.comIn scope2026-11-14
cf-190-93-248-211.cloudflare.comIn scope2026-11-14
cf-190-93-248-212.cloudflare.comIn scope2026-11-14
cf-190-93-248-213.cloudflare.comIn scope2026-11-14
cf-190-93-248-214.cloudflare.comIn scope2026-11-14
cf-190-93-248-215.cloudflare.comIn scope2026-11-14
cf-190-93-248-216.cloudflare.comIn scope2026-11-14
cf-190-93-248-217.cloudflare.comIn scope2026-11-14
cf-190-93-248-218.cloudflare.comIn scope2026-11-14
cf-190-93-248-219.cloudflare.comIn scope2026-11-14
cf-190-93-248-22.cloudflare.comIn scope2026-11-14
cf-190-93-248-220.cloudflare.comIn scope2026-11-14
cf-190-93-248-221.cloudflare.comIn scope2026-11-14
cf-190-93-248-222.cloudflare.comIn scope2026-11-14
cf-190-93-248-223.cloudflare.comIn scope2026-11-14
cf-190-93-248-224.cloudflare.comIn scope2026-11-14
cf-190-93-248-225.cloudflare.comIn scope2026-11-14
cf-190-93-248-226.cloudflare.comIn scope2026-11-14
cf-190-93-248-227.cloudflare.comIn scope2026-11-14
cf-190-93-248-228.cloudflare.comIn scope2026-11-14
cf-190-93-248-229.cloudflare.comIn scope2026-11-14
cf-190-93-248-23.cloudflare.comIn scope2026-11-14
cf-190-93-248-230.cloudflare.comIn scope2026-11-14
cf-190-93-248-231.cloudflare.comIn scope2026-11-14
cf-190-93-248-232.cloudflare.comIn scope2026-11-14
cf-190-93-248-233.cloudflare.comIn scope2026-11-14
cf-190-93-248-234.cloudflare.comIn scope2026-11-14
cf-190-93-248-235.cloudflare.comIn scope2026-11-14
cf-190-93-248-236.cloudflare.comIn scope2026-11-14
cf-190-93-248-237.cloudflare.comIn scope2026-11-14
cf-190-93-248-238.cloudflare.comIn scope2026-11-14
cf-190-93-248-239.cloudflare.comIn scope2026-11-14
cf-190-93-248-24.cloudflare.comIn scope2026-11-14
cf-190-93-248-240.cloudflare.comIn scope2026-11-14
cf-190-93-248-241.cloudflare.comIn scope2026-11-14
cf-190-93-248-242.cloudflare.comIn scope2026-11-14
cf-190-93-248-243.cloudflare.comIn scope2026-11-14
cf-190-93-248-244.cloudflare.comIn scope2026-11-14
cf-190-93-248-245.cloudflare.comIn scope2026-11-14
cf-190-93-248-246.cloudflare.comIn scope2026-11-14
cf-190-93-248-247.cloudflare.comIn scope2026-11-14
cf-190-93-248-248.cloudflare.comIn scope2026-11-14
cf-190-93-248-249.cloudflare.comIn scope2026-11-14
cf-190-93-248-25.cloudflare.comIn scope2026-11-14
cf-190-93-248-250.cloudflare.comIn scope2026-11-14
cf-190-93-248-251.cloudflare.comIn scope2026-11-14
cf-190-93-248-252.cloudflare.comIn scope2026-11-14
cf-190-93-248-253.cloudflare.comIn scope2026-11-14
cf-190-93-248-254.cloudflare.comIn scope2026-11-14
cf-190-93-248-26.cloudflare.comIn scope2026-11-14
cf-190-93-248-27.cloudflare.comIn scope2026-11-14
cf-190-93-248-28.cloudflare.comIn scope2026-11-14
cf-190-93-248-29.cloudflare.comIn scope2026-11-14
cf-190-93-248-30.cloudflare.comIn scope2026-11-14
cf-190-93-248-31.cloudflare.comIn scope2026-11-14
cf-190-93-248-32.cloudflare.comIn scope2026-11-14
cf-190-93-248-33.cloudflare.comIn scope2026-11-14
cf-190-93-248-34.cloudflare.comIn scope2026-11-14
cf-190-93-248-35.cloudflare.comIn scope2026-11-14
cf-190-93-248-36.cloudflare.comIn scope2026-11-14
cf-190-93-248-37.cloudflare.comIn scope2026-11-14
cf-190-93-248-38.cloudflare.comIn scope2026-11-14
cf-190-93-248-39.cloudflare.comIn scope2026-11-14
cf-190-93-248-4.cloudflare.comIn scope2026-11-14
cf-190-93-248-40.cloudflare.comIn scope2026-11-14
cf-190-93-248-41.cloudflare.comIn scope2026-11-14
cf-190-93-248-42.cloudflare.comIn scope2026-11-14
cf-190-93-248-43.cloudflare.comIn scope2026-11-14
cf-190-93-248-44.cloudflare.comIn scope2026-11-14
cf-190-93-248-45.cloudflare.comIn scope2026-11-14
cf-190-93-248-46.cloudflare.comIn scope2026-11-14
cf-190-93-248-47.cloudflare.comIn scope2026-11-14
cf-190-93-248-48.cloudflare.comIn scope2026-11-14
cf-190-93-248-49.cloudflare.comIn scope2026-11-14
cf-190-93-248-5.cloudflare.comIn scope2026-11-14
cf-190-93-248-50.cloudflare.comIn scope2026-11-14
cf-190-93-248-51.cloudflare.comIn scope2026-11-14
cf-190-93-248-52.cloudflare.comIn scope2026-11-14
cf-190-93-248-53.cloudflare.comIn scope2026-11-14
cf-190-93-248-54.cloudflare.comIn scope2026-11-14
cf-190-93-248-55.cloudflare.comIn scope2026-11-14
cf-190-93-248-56.cloudflare.comIn scope2026-11-14
cf-190-93-248-57.cloudflare.comIn scope2026-11-14
cf-190-93-248-58.cloudflare.comIn scope2026-11-14
cf-190-93-248-59.cloudflare.comIn scope2026-11-14
cf-190-93-248-6.cloudflare.comIn scope2026-11-14
cf-190-93-248-60.cloudflare.comIn scope2026-11-14
cf-190-93-248-61.cloudflare.comIn scope2026-11-14
cf-190-93-248-62.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.