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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-190-93-246-202.cloudflare.comIn scope2026-11-14
cf-190-93-246-203.cloudflare.comIn scope2026-11-14
cf-190-93-246-204.cloudflare.comIn scope2026-11-14
cf-190-93-246-205.cloudflare.comIn scope2026-11-14
cf-190-93-246-206.cloudflare.comIn scope2026-11-14
cf-190-93-246-207.cloudflare.comIn scope2026-11-14
cf-190-93-246-208.cloudflare.comIn scope2026-11-14
cf-190-93-246-209.cloudflare.comIn scope2026-11-14
cf-190-93-246-21.cloudflare.comIn scope2026-11-14
cf-190-93-246-210.cloudflare.comIn scope2026-11-14
cf-190-93-246-211.cloudflare.comIn scope2026-11-14
cf-190-93-246-212.cloudflare.comIn scope2026-11-14
cf-190-93-246-213.cloudflare.comIn scope2026-11-14
cf-190-93-246-214.cloudflare.comIn scope2026-11-14
cf-190-93-246-215.cloudflare.comIn scope2026-11-14
cf-190-93-246-216.cloudflare.comIn scope2026-11-14
cf-190-93-246-217.cloudflare.comIn scope2026-11-14
cf-190-93-246-218.cloudflare.comIn scope2026-11-14
cf-190-93-246-219.cloudflare.comIn scope2026-11-14
cf-190-93-246-22.cloudflare.comIn scope2026-11-14
cf-190-93-246-220.cloudflare.comIn scope2026-11-14
cf-190-93-246-221.cloudflare.comIn scope2026-11-14
cf-190-93-246-222.cloudflare.comIn scope2026-11-14
cf-190-93-246-223.cloudflare.comIn scope2026-11-14
cf-190-93-246-224.cloudflare.comIn scope2026-11-14
cf-190-93-246-225.cloudflare.comIn scope2026-11-14
cf-190-93-246-226.cloudflare.comIn scope2026-11-14
cf-190-93-246-227.cloudflare.comIn scope2026-11-14
cf-190-93-246-228.cloudflare.comIn scope2026-11-14
cf-190-93-246-229.cloudflare.comIn scope2026-11-14
cf-190-93-246-23.cloudflare.comIn scope2026-11-14
cf-190-93-246-230.cloudflare.comIn scope2026-11-14
cf-190-93-246-231.cloudflare.comIn scope2026-11-14
cf-190-93-246-232.cloudflare.comIn scope2026-11-14
cf-190-93-246-233.cloudflare.comIn scope2026-11-14
cf-190-93-246-234.cloudflare.comIn scope2026-11-14
cf-190-93-246-235.cloudflare.comIn scope2026-11-14
cf-190-93-246-236.cloudflare.comIn scope2026-11-14
cf-190-93-246-237.cloudflare.comIn scope2026-11-14
cf-190-93-246-238.cloudflare.comIn scope2026-11-14
cf-190-93-246-239.cloudflare.comIn scope2026-11-14
cf-190-93-246-24.cloudflare.comIn scope2026-11-14
cf-190-93-246-240.cloudflare.comIn scope2026-11-14
cf-190-93-246-241.cloudflare.comIn scope2026-11-14
cf-190-93-246-242.cloudflare.comIn scope2026-11-14
cf-190-93-246-243.cloudflare.comIn scope2026-11-14
cf-190-93-246-244.cloudflare.comIn scope2026-11-14
cf-190-93-246-245.cloudflare.comIn scope2026-11-14
cf-190-93-246-246.cloudflare.comIn scope2026-11-14
cf-190-93-246-247.cloudflare.comIn scope2026-11-14
cf-190-93-246-248.cloudflare.comIn scope2026-11-14
cf-190-93-246-249.cloudflare.comIn scope2026-11-14
cf-190-93-246-25.cloudflare.comIn scope2026-11-14
cf-190-93-246-250.cloudflare.comIn scope2026-11-14
cf-190-93-246-251.cloudflare.comIn scope2026-11-14
cf-190-93-246-252.cloudflare.comIn scope2026-11-14
cf-190-93-246-253.cloudflare.comIn scope2026-11-14
cf-190-93-246-254.cloudflare.comIn scope2026-11-14
cf-190-93-246-26.cloudflare.comIn scope2026-11-14
cf-190-93-246-27.cloudflare.comIn scope2026-11-14
cf-190-93-246-28.cloudflare.comIn scope2026-11-14
cf-190-93-246-29.cloudflare.comIn scope2026-11-14
cf-190-93-246-30.cloudflare.comIn scope2026-11-14
cf-190-93-246-31.cloudflare.comIn scope2026-11-14
cf-190-93-246-32.cloudflare.comIn scope2026-11-14
cf-190-93-246-33.cloudflare.comIn scope2026-11-14
cf-190-93-246-34.cloudflare.comIn scope2026-11-14
cf-190-93-246-35.cloudflare.comIn scope2026-11-14
cf-190-93-246-36.cloudflare.comIn scope2026-11-14
cf-190-93-246-37.cloudflare.comIn scope2026-11-14
cf-190-93-246-38.cloudflare.comIn scope2026-11-14
cf-190-93-246-39.cloudflare.comIn scope2026-11-14
cf-190-93-246-4.cloudflare.comIn scope2026-11-14
cf-190-93-246-40.cloudflare.comIn scope2026-11-14
cf-190-93-246-41.cloudflare.comIn scope2026-11-14
cf-190-93-246-42.cloudflare.comIn scope2026-11-14
cf-190-93-246-43.cloudflare.comIn scope2026-11-14
cf-190-93-246-44.cloudflare.comIn scope2026-11-14
cf-190-93-246-45.cloudflare.comIn scope2026-11-14
cf-190-93-246-46.cloudflare.comIn scope2026-11-14
cf-190-93-246-47.cloudflare.comIn scope2026-11-14
cf-190-93-246-48.cloudflare.comIn scope2026-11-14
cf-190-93-246-49.cloudflare.comIn scope2026-11-14
cf-190-93-246-5.cloudflare.comIn scope2026-11-14
cf-190-93-246-50.cloudflare.comIn scope2026-11-14
cf-190-93-246-51.cloudflare.comIn scope2026-11-14
cf-190-93-246-52.cloudflare.comIn scope2026-11-14
cf-190-93-246-53.cloudflare.comIn scope2026-11-14
cf-190-93-246-54.cloudflare.comIn scope2026-11-14
cf-190-93-246-55.cloudflare.comIn scope2026-11-14
cf-190-93-246-56.cloudflare.comIn scope2026-11-14
cf-190-93-246-57.cloudflare.comIn scope2026-11-14
cf-190-93-246-58.cloudflare.comIn scope2026-11-14
cf-190-93-246-59.cloudflare.comIn scope2026-11-14
cf-190-93-246-6.cloudflare.comIn scope2026-11-14
cf-190-93-246-60.cloudflare.comIn scope2026-11-14
cf-190-93-246-61.cloudflare.comIn scope2026-11-14
cf-190-93-246-62.cloudflare.comIn scope2026-11-14
cf-190-93-246-63.cloudflare.comIn scope2026-11-14
cf-190-93-246-64.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.