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KAYAK

Bug bounty on HackerOne kayak.com

Accepting reports
Top reward
$5,000
Top severity paid
Critical
Assets in scope
12
Public CVEs
0
Last change
No changes yet

At a glance

What to know before you start testing.

Pays up to $5,000
for critical bugs.
Report on HackerOne
Submit through the program page.
Publish after a fix
Coordinate the timing with the company.

Rewards

What HackerOne lists as the payout for each severity.

Severity Reward
Critical $5,000
High $1,500
Medium $500
Low $100

Scope

12 assets you may test, 7 excluded.

Web 9

  • business.kayak.com Critical
  • kayak.ai Critical
  • www.cheapflights.com Critical
  • www.checkfelix.com Critical
  • www.hotelscombined.com Critical
  • www.kayak.com Critical
  • www.momondo.com Critical
  • www.mundi.com.br Critical
  • www.swoodoo.com Critical

Android apps 1

  • com.kayak.android Critical

iOS apps 1

  • com.kayak.travel Critical

Wildcard domains 1

  • *.kayak.com Critical
Out of scope (7)
  • affiliates.kayak.com
  • cruises.kayak.com
  • kayak.com/guides/*
  • kayak.com/hotelowner/*
  • kayak.com/moira/ehoe/*
  • klassereise.checkfelix.com
  • *.kayakairplanemode.com

Rules

What the policy asks of you, and the bug types it won't reward, quoted from KAYAK (via HackerOne)'s policy. "We" in these lines means the program, not this site.

While testing

  • Use a custom HTTP header and mention that in your report. For example, a header that includes your username: X-Bug-Bounty:HackerOne-your-username.
  • When making an account or reservation, please use your HackerOne Email Alias (e.g., [email protected]), so that we can properly identify you
  • Do not compromise any customer accounts or data. Never attempt to view, modify, or damage data belonging to others. If you need to test a vulnerability, create an account.
  • Do not use automated tools that could generate significant traffic and possibly impair the functioning of our services.
  • Do not discuss or post details of your vulnerability outside of the HackerOne platform before it has been approved for disclosure.
  • Please communicate with our security team via HackerOne.
  • We may change the terms of this program at any time.

Not accepted

  • Denial of service, distributed denial of service, or other availability attacks.
  • Any techniques related to web scraping
  • Brute force attacks against passwords, hash secrets etc.
  • Physical attacks against any KAYAK office or data center.
  • Social engineering, for example phishing or calling, of any KAYAK employee, contractor or agent.
  • SSL configuration
  • HTTP response headers including cookie configuration, Content security policy, etc.
  • Logout CSRF and CSRF on endpoints that do not change user state. MITM attacks against a user's CSRF token.
  • Issues with any site or application not explicitly listed as in-scope.
  • Problems found in our iOS apps before v205 and Android apps before v175
  • Third-party content served on HTTP when KAYAK is accessed on HTTPS. Particularly with ad networks we have no direct control.
  • Clickjacking (except rare, highly sensitive cases)
  • Absence of SPF, DKIM, DMARC or domain lock records
  • DNSSEC-related reports
  • Lack of "best practices" that do not impose a vulnerability that can be leveraged (please send PoC) e.g. session expiration, magic link expiration
  • Missing or not obviously visible rate limiting - please do not test our endpoints for this as this makes noise that we usually pick up and act on
  • Vulnerabilities in third-party software and systems that we use. We are patching components on a regular basis according to our risk assessments.
  • Severity level is at the sole discretion of the KAYAK security team.

Summarised with AI from the program policy on HackerOne, and checked word for word against it. Read the original

Changes

Tracked since 11 Nov 2026. Last checked 43 minutes ago.

No changes yet. When the rewards or scope move, you will see it here and in the RSS feed.

Public CVEs

Published vulnerabilities in this vendor's products, from the NVD.

Search NVD

No CVEs matched yet. We match NVD records by vendor name, so products sold under another name can be missing.

Original policy

Copied from hackerone.com on 12 Nov 2026. The summaries on this page are made from it; the live page may have changed since.

KAYAK is committed to working with security experts across the world to stay up to date with the latest security techniques. If you have discovered a security issue that you believe we should know about, we'd welcome working with you.

Scope

Scope is outlined in the structured scope section. Please do not submit the same report for multiple domains. Only one report will be accepted.

Eligible Vulnerabilities

  • You must be the first person to report a vulnerability.
  • Please share with us the full details of any problem you find.
  • The vulnerability must be on an in-scope site or application.
  • Qualification of vulnerabilities is at the sole discretion of the KAYAK security team.
  • The vulnerability must be reproducible on a reasonably recent version of the according client (e.g., at least Microsoft Edge, Chrome 111, Firefox 111, Safari 15)
  • Vulnerabilities raised on the Android or iOS apps must be against the latest app store versions

Non-Qualifying Vulnerabilities and Exclusions

  • Clarification - NEW We do not take any responsibility for links to third-party/off-site content including social media profiles that may have been owned by us previously or be trying to impersonate us. This includes any links you find on our assets in all areas of the products including headers and footers.
  • Denial of service, distributed denial of service, or other availability attacks.
  • Any techniques related to web scraping
  • Brute force attacks against passwords, hash secrets etc.
  • Physical attacks against any KAYAK office or data center.
  • Social engineering, for example phishing or calling, of any KAYAK employee, contractor or agent.
  • One of the following issues without a proof-of-concept that successfully exploits the issue:
  • SSL configuration
  • HTTP response headers including cookie configuration, Content security policy, etc.
  • Logout CSRF and CSRF on endpoints that do not change user state. MITM attacks against a user's CSRF token.
  • Issues with any site or application not explicitly listed as in-scope.
  • Problems found in our iOS apps before v205 and Android apps before v175
  • Issues introduced by third-party components that have not been fixed by the vendor yet. This also includes vulnerabilities introduced by content served through one of our ad networks.
  • Third-party content served on HTTP when KAYAK is accessed on HTTPS. Particularly with ad networks we have no direct control.
  • Clickjacking (except rare, highly sensitive cases)
  • Attacks that require a mobile phone or tablet to be "rooted". Attacks that assume that a user intentionally or unintentionally disabled standard OS security features.
  • Absence of SPF, DKIM, DMARC or domain lock records
  • DNSSEC-related reports
  • Lack of "best practices" that do not impose a vulnerability that can be leveraged (please send PoC) e.g. session expiration, magic link expiration
  • Missing or not obviously visible rate limiting - please do not test our endpoints for this as this makes noise that we usually pick up and act on
  • Vulnerabilities in third-party software and systems that we use. We are patching components on a regular basis according to our risk assessments.
  • Vulnerable domain/DNS configuration are only in scope as long as they involve our core assets as listed in this program. For example, a domain takeover of some-service.kayak.com is a valid finding while a domain takeover of any other domain owned by us but not part of our core assets is not.
  • We cannot reward or do business with any individual on any U.S sanction lists or any individual residing in any country on any U.S. sanctions lists. This includes residents of Cuba, Sudan, North Korea, Iran, Syria or Russia.
  • Severity level is at the sole discretion of the KAYAK security team.

Rules of Engagement

  • Use a custom HTTP header and mention that in your report. For example, a header that includes your username: X-Bug-Bounty:HackerOne-your-username.
  • When making an account or reservation, please use your HackerOne Email Alias (e.g., [email protected]), so that we can properly identify you
  • Do not compromise any customer accounts or data. Never attempt to view, modify, or damage data belonging to others. If you need to test a vulnerability, create an account.
  • Do not use automated tools that could generate significant traffic and possibly impair the functioning of our services.
  • Do not discuss or post details of your vulnerability outside of the HackerOne platform before it has been approved for disclosure.
  • Do not attempt denial-of-service attacks. Keep your automated scanning to 10 requests per second or less.
  • Please communicate with our security team via HackerOne.
  • We may change the terms of this program at any time.

For any bugs pertaining to Information Disclosure, please do not capture and retain any personally identifiable or sensitive personal information (PII) during the course of your research. If you inadvertently view or change any PII not related to your own account, please stop testing immediately and submit a report with reproduction steps so that our team can evaluate the potential business impact of any exposed PII.

When possible, please employ methods that confirm elevated access without exposing PII, for example:

  • Screenshots of navigation bar options or pages without PII that weren’t originally viewable.
  • Improper access to another account you yourself control
  • (in the case of gaining access to a company server) Access to common default files present on any server

Attributes of a Good Report and Bug Bounty Rewards

  • Please provide a detailed report with precise explanations. Please include screenshots, proof-of-concept code, and steps to reproduce.
  • Bug bounty rewards are solely at KAYAK's discretion, based on the severity and creativity of the bug.
  • You must adhere to HackerOne's Disclosure Guidelines and everything outlined in this policy. We are committed to ensuring the privacy and safety of our users. If you think that you have discovered a security vulnerability on our web site or within our mobile apps we appreciate your help in disclosing the issue to us. Please do this responsibly by giving us the opportunity to investigate and fix the vulnerability in a timely fashion before publicly disclosing it. Security vulnerability reports will be treated as high priority. We will validate and fix vulnerabilities in accordance with our commitment to security and privacy.