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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-190-93-252-6.cloudflare.comIn scope2026-11-14
cf-190-93-252-60.cloudflare.comIn scope2026-11-14
cf-190-93-252-61.cloudflare.comIn scope2026-11-14
cf-190-93-252-62.cloudflare.comIn scope2026-11-14
cf-190-93-252-63.cloudflare.comIn scope2026-11-14
cf-190-93-252-64.cloudflare.comIn scope2026-11-14
cf-190-93-252-65.cloudflare.comIn scope2026-11-14
cf-190-93-252-66.cloudflare.comIn scope2026-11-14
cf-190-93-252-67.cloudflare.comIn scope2026-11-14
cf-190-93-252-68.cloudflare.comIn scope2026-11-14
cf-190-93-252-69.cloudflare.comIn scope2026-11-14
cf-190-93-252-7.cloudflare.comIn scope2026-11-14
cf-190-93-252-70.cloudflare.comIn scope2026-11-14
cf-190-93-252-71.cloudflare.comIn scope2026-11-14
cf-190-93-252-72.cloudflare.comIn scope2026-11-14
cf-190-93-252-73.cloudflare.comIn scope2026-11-14
cf-190-93-252-74.cloudflare.comIn scope2026-11-14
cf-190-93-252-75.cloudflare.comIn scope2026-11-14
cf-190-93-252-76.cloudflare.comIn scope2026-11-14
cf-190-93-252-77.cloudflare.comIn scope2026-11-14
cf-190-93-252-78.cloudflare.comIn scope2026-11-14
cf-190-93-252-79.cloudflare.comIn scope2026-11-14
cf-190-93-252-8.cloudflare.comIn scope2026-11-14
cf-190-93-252-80.cloudflare.comIn scope2026-11-14
cf-190-93-252-81.cloudflare.comIn scope2026-11-14
cf-190-93-252-82.cloudflare.comIn scope2026-11-14
cf-190-93-252-83.cloudflare.comIn scope2026-11-14
cf-190-93-252-84.cloudflare.comIn scope2026-11-14
cf-190-93-252-85.cloudflare.comIn scope2026-11-14
cf-190-93-252-86.cloudflare.comIn scope2026-11-14
cf-190-93-252-87.cloudflare.comIn scope2026-11-14
cf-190-93-252-88.cloudflare.comIn scope2026-11-14
cf-190-93-252-89.cloudflare.comIn scope2026-11-14
cf-190-93-252-9.cloudflare.comIn scope2026-11-14
cf-190-93-252-90.cloudflare.comIn scope2026-11-14
cf-190-93-252-91.cloudflare.comIn scope2026-11-14
cf-190-93-252-92.cloudflare.comIn scope2026-11-14
cf-190-93-252-93.cloudflare.comIn scope2026-11-14
cf-190-93-252-94.cloudflare.comIn scope2026-11-14
cf-190-93-252-95.cloudflare.comIn scope2026-11-14
cf-190-93-252-96.cloudflare.comIn scope2026-11-14
cf-190-93-252-97.cloudflare.comIn scope2026-11-14
cf-190-93-252-98.cloudflare.comIn scope2026-11-14
cf-190-93-252-99.cloudflare.comIn scope2026-11-14
cf-190-93-253-10.cloudflare.comIn scope2026-11-14
cf-190-93-253-100.cloudflare.comIn scope2026-11-14
cf-190-93-253-101.cloudflare.comIn scope2026-11-14
cf-190-93-253-102.cloudflare.comIn scope2026-11-14
cf-190-93-253-103.cloudflare.comIn scope2026-11-14
cf-190-93-253-104.cloudflare.comIn scope2026-11-14
cf-190-93-253-105.cloudflare.comIn scope2026-11-14
cf-190-93-253-106.cloudflare.comIn scope2026-11-14
cf-190-93-253-107.cloudflare.comIn scope2026-11-14
cf-190-93-253-108.cloudflare.comIn scope2026-11-14
cf-190-93-253-109.cloudflare.comIn scope2026-11-14
cf-190-93-253-11.cloudflare.comIn scope2026-11-14
cf-190-93-253-110.cloudflare.comIn scope2026-11-14
cf-190-93-253-111.cloudflare.comIn scope2026-11-14
cf-190-93-253-112.cloudflare.comIn scope2026-11-14
cf-190-93-253-113.cloudflare.comIn scope2026-11-14
cf-190-93-253-114.cloudflare.comIn scope2026-11-14
cf-190-93-253-115.cloudflare.comIn scope2026-11-14
cf-190-93-253-116.cloudflare.comIn scope2026-11-14
cf-190-93-253-117.cloudflare.comIn scope2026-11-14
cf-190-93-253-118.cloudflare.comIn scope2026-11-14
cf-190-93-253-119.cloudflare.comIn scope2026-11-14
cf-190-93-253-12.cloudflare.comIn scope2026-11-14
cf-190-93-253-120.cloudflare.comIn scope2026-11-14
cf-190-93-253-121.cloudflare.comIn scope2026-11-14
cf-190-93-253-122.cloudflare.comIn scope2026-11-14
cf-190-93-253-123.cloudflare.comIn scope2026-11-14
cf-190-93-253-124.cloudflare.comIn scope2026-11-14
cf-190-93-253-125.cloudflare.comIn scope2026-11-14
cf-190-93-253-126.cloudflare.comIn scope2026-11-14
cf-190-93-253-127.cloudflare.comIn scope2026-11-14
cf-190-93-253-128.cloudflare.comIn scope2026-11-14
cf-190-93-253-129.cloudflare.comIn scope2026-11-14
cf-190-93-253-13.cloudflare.comIn scope2026-11-14
cf-190-93-253-130.cloudflare.comIn scope2026-11-14
cf-190-93-253-131.cloudflare.comIn scope2026-11-14
cf-190-93-253-132.cloudflare.comIn scope2026-11-14
cf-190-93-253-133.cloudflare.comIn scope2026-11-14
cf-190-93-253-134.cloudflare.comIn scope2026-11-14
cf-190-93-253-135.cloudflare.comIn scope2026-11-14
cf-190-93-253-136.cloudflare.comIn scope2026-11-14
cf-190-93-253-137.cloudflare.comIn scope2026-11-14
cf-190-93-253-138.cloudflare.comIn scope2026-11-14
cf-190-93-253-139.cloudflare.comIn scope2026-11-14
cf-190-93-253-14.cloudflare.comIn scope2026-11-14
cf-190-93-253-140.cloudflare.comIn scope2026-11-14
cf-190-93-253-141.cloudflare.comIn scope2026-11-14
cf-190-93-253-142.cloudflare.comIn scope2026-11-14
cf-190-93-253-143.cloudflare.comIn scope2026-11-14
cf-190-93-253-144.cloudflare.comIn scope2026-11-14
cf-190-93-253-145.cloudflare.comIn scope2026-11-14
cf-190-93-253-146.cloudflare.comIn scope2026-11-14
cf-190-93-253-147.cloudflare.comIn scope2026-11-14
cf-190-93-253-148.cloudflare.comIn scope2026-11-14
cf-190-93-253-149.cloudflare.comIn scope2026-11-14
cf-190-93-253-15.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.