Bug bounty reports15,219
Publicly disclosed HackerOne reports, with the platform's own outcome and severity.
| Report | Status | Weakness | Severity | Disclosed | Bounty | Votes |
|---|---|---|---|---|---|---|
| Stealing xoxs-tokens using weak postMessage / call-popup redirect to current team domainAnalysed#207170 | Valid | Misconfiguration and Insecure Design | – | 2017-02-28 | – | 120 |
| Many Slack teams can be joined by abusing an improperly configured support@ inboxAnalysed#239623 | Valid | Authentication | – | 2017-10-21 | – | 88 |
| Eavesdropping on private Slack callsAnalysed#184698 | Valid | Authentication | High | 2017-02-08 | $1,000 | 68 |
| The Custom Emoji Page has a Reflected XSSAnalysed#258198 | Valid | Cross-site Scripting | High | 2017-09-24 | – | 56 |
| Store XSSAnalysed#187410 | Valid | Cross-site Scripting | High | 2017-01-01 | – | 44 |
| Bypass two-factor authenticationAnalysed#121696 | Valid | Authentication | – | 2017-11-18 | – | 36 |
| Access of Android protected components via embedded intentAnalysed#200427 | Valid | Access Control | Critical | 2017-07-17 | – | 31 |
| Race Condition in account surveyAnalysed#165570 | Valid | Misconfiguration and Insecure Design | – | 2017-11-12 | – | 29 |
| Subdomain takeover on podcasts.slack-core.comAnalysed#195350 | Valid | Cross-site Scripting | Low | 2017-01-04 | $100 | 27 |
| [Screenhero] Subdomain takeoverAnalysed#142096 | Valid | Misconfiguration and Insecure Design | – | 2017-01-21 | – | 23 |
| Bypass to postMessage origin validation via FTP#210654 | Valid | Cross-site Scripting | High | 2017-04-21 | – | 15 |
| Code Injection in Slack's Windows Desktop Client leads to Privilege Escalation#162955 | Valid | Command and Code Injection | – | 2017-07-14 | – | 14 |
| dom xss in https://www.slackatwork.com#196624 | Valid | Cross-site Scripting | Low | 2017-03-02 | – | 13 |
| a stored xss issue in https://files.slack.com#149011 | Valid | Cross-site Scripting | – | 2017-06-25 | $500 | 9 |
| "a stored xss issue in share post menu"#148848 | Valid | Cross-site Scripting | – | 2017-06-25 | $500 | 8 |
Status and severity are HackerOne's. “Access stated” is what the title says; “Access needed” and techniques come from CyberSIXT's analysis of the public report, where there is one, which can be wrong. Data as of 2026-11-15.