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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-190-93-250-108.cloudflare.comIn scope2026-11-14
cf-190-93-250-109.cloudflare.comIn scope2026-11-14
cf-190-93-250-11.cloudflare.comIn scope2026-11-14
cf-190-93-250-110.cloudflare.comIn scope2026-11-14
cf-190-93-250-111.cloudflare.comIn scope2026-11-14
cf-190-93-250-112.cloudflare.comIn scope2026-11-14
cf-190-93-250-113.cloudflare.comIn scope2026-11-14
cf-190-93-250-114.cloudflare.comIn scope2026-11-14
cf-190-93-250-115.cloudflare.comIn scope2026-11-14
cf-190-93-250-116.cloudflare.comIn scope2026-11-14
cf-190-93-250-117.cloudflare.comIn scope2026-11-14
cf-190-93-250-118.cloudflare.comIn scope2026-11-14
cf-190-93-250-119.cloudflare.comIn scope2026-11-14
cf-190-93-250-12.cloudflare.comIn scope2026-11-14
cf-190-93-250-120.cloudflare.comIn scope2026-11-14
cf-190-93-250-121.cloudflare.comIn scope2026-11-14
cf-190-93-250-122.cloudflare.comIn scope2026-11-14
cf-190-93-250-123.cloudflare.comIn scope2026-11-14
cf-190-93-250-124.cloudflare.comIn scope2026-11-14
cf-190-93-250-125.cloudflare.comIn scope2026-11-14
cf-190-93-250-126.cloudflare.comIn scope2026-11-14
cf-190-93-250-127.cloudflare.comIn scope2026-11-14
cf-190-93-250-128.cloudflare.comIn scope2026-11-14
cf-190-93-250-129.cloudflare.comIn scope2026-11-14
cf-190-93-250-13.cloudflare.comIn scope2026-11-14
cf-190-93-250-130.cloudflare.comIn scope2026-11-14
cf-190-93-250-131.cloudflare.comIn scope2026-11-14
cf-190-93-250-132.cloudflare.comIn scope2026-11-14
cf-190-93-250-133.cloudflare.comIn scope2026-11-14
cf-190-93-250-134.cloudflare.comIn scope2026-11-14
cf-190-93-250-135.cloudflare.comIn scope2026-11-14
cf-190-93-250-136.cloudflare.comIn scope2026-11-14
cf-190-93-250-137.cloudflare.comIn scope2026-11-14
cf-190-93-250-138.cloudflare.comIn scope2026-11-14
cf-190-93-250-139.cloudflare.comIn scope2026-11-14
cf-190-93-250-14.cloudflare.comIn scope2026-11-14
cf-190-93-250-140.cloudflare.comIn scope2026-11-14
cf-190-93-250-141.cloudflare.comIn scope2026-11-14
cf-190-93-250-142.cloudflare.comIn scope2026-11-14
cf-190-93-250-143.cloudflare.comIn scope2026-11-14
cf-190-93-250-144.cloudflare.comIn scope2026-11-14
cf-190-93-250-145.cloudflare.comIn scope2026-11-14
cf-190-93-250-146.cloudflare.comIn scope2026-11-14
cf-190-93-250-147.cloudflare.comIn scope2026-11-14
cf-190-93-250-148.cloudflare.comIn scope2026-11-14
cf-190-93-250-149.cloudflare.comIn scope2026-11-14
cf-190-93-250-15.cloudflare.comIn scope2026-11-14
cf-190-93-250-150.cloudflare.comIn scope2026-11-14
cf-190-93-250-151.cloudflare.comIn scope2026-11-14
cf-190-93-250-152.cloudflare.comIn scope2026-11-14
cf-190-93-250-153.cloudflare.comIn scope2026-11-14
cf-190-93-250-154.cloudflare.comIn scope2026-11-14
cf-190-93-250-155.cloudflare.comIn scope2026-11-14
cf-190-93-250-156.cloudflare.comIn scope2026-11-14
cf-190-93-250-157.cloudflare.comIn scope2026-11-14
cf-190-93-250-158.cloudflare.comIn scope2026-11-14
cf-190-93-250-159.cloudflare.comIn scope2026-11-14
cf-190-93-250-16.cloudflare.comIn scope2026-11-14
cf-190-93-250-160.cloudflare.comIn scope2026-11-14
cf-190-93-250-161.cloudflare.comIn scope2026-11-14
cf-190-93-250-162.cloudflare.comIn scope2026-11-14
cf-190-93-250-163.cloudflare.comIn scope2026-11-14
cf-190-93-250-164.cloudflare.comIn scope2026-11-14
cf-190-93-250-165.cloudflare.comIn scope2026-11-14
cf-190-93-250-166.cloudflare.comIn scope2026-11-14
cf-190-93-250-167.cloudflare.comIn scope2026-11-14
cf-190-93-250-168.cloudflare.comIn scope2026-11-14
cf-190-93-250-169.cloudflare.comIn scope2026-11-14
cf-190-93-250-17.cloudflare.comIn scope2026-11-14
cf-190-93-250-170.cloudflare.comIn scope2026-11-14
cf-190-93-250-171.cloudflare.comIn scope2026-11-14
cf-190-93-250-172.cloudflare.comIn scope2026-11-14
cf-190-93-250-173.cloudflare.comIn scope2026-11-14
cf-190-93-250-174.cloudflare.comIn scope2026-11-14
cf-190-93-250-175.cloudflare.comIn scope2026-11-14
cf-190-93-250-176.cloudflare.comIn scope2026-11-14
cf-190-93-250-177.cloudflare.comIn scope2026-11-14
cf-190-93-250-178.cloudflare.comIn scope2026-11-14
cf-190-93-250-179.cloudflare.comIn scope2026-11-14
cf-190-93-250-18.cloudflare.comIn scope2026-11-14
cf-190-93-250-180.cloudflare.comIn scope2026-11-14
cf-190-93-250-181.cloudflare.comIn scope2026-11-14
cf-190-93-250-182.cloudflare.comIn scope2026-11-14
cf-190-93-250-183.cloudflare.comIn scope2026-11-14
cf-190-93-250-184.cloudflare.comIn scope2026-11-14
cf-190-93-250-185.cloudflare.comIn scope2026-11-14
cf-190-93-250-186.cloudflare.comIn scope2026-11-14
cf-190-93-250-187.cloudflare.comIn scope2026-11-14
cf-190-93-250-188.cloudflare.comIn scope2026-11-14
cf-190-93-250-189.cloudflare.comIn scope2026-11-14
cf-190-93-250-19.cloudflare.comIn scope2026-11-14
cf-190-93-250-190.cloudflare.comIn scope2026-11-14
cf-190-93-250-191.cloudflare.comIn scope2026-11-14
cf-190-93-250-192.cloudflare.comIn scope2026-11-14
cf-190-93-250-193.cloudflare.comIn scope2026-11-14
cf-190-93-250-194.cloudflare.comIn scope2026-11-14
cf-190-93-250-195.cloudflare.comIn scope2026-11-14
cf-190-93-250-196.cloudflare.comIn scope2026-11-14
cf-190-93-250-197.cloudflare.comIn scope2026-11-14
cf-190-93-250-198.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.