Prosper
Disclosed Sep 17, 20251 year ago17,605,276 accountsConfirmed
Hackers steal data of 17.6 million Prosper accounts including SSNs
Prosper told the SEC it identified unauthorized access to systems containing confidential information on September 1, 2025; attackers queried customer and applicant databases and took data including SSNs. Have I Been Pwned said 17.6 million accounts were affected.
What is known
| People affected | 17,605,276 (accounts in the leaked data, per Have I Been Pwned) |
|---|---|
| Disclosed | Sep 17, 2025 |
| Discovered | Sep 1, 2025 |
| Happened | Sep 1, 2025 |
| Attack | Hacking |
| Data exposed | Financial, Dates of birth, Emails, Employment, Government IDs, IP addresses, Names, Addresses, Social Security numbers, Other |
| Sector | Finance · US |
| Status | Confirmed |
| Check your email | Have I Been Pwned |
Sources
| Source | |
|---|---|
| Have I Been Pwned: Prosperhaveibeenpwned.com · Aggregator | Aggregator |
| Prosper disclosureprosper.com · The organization | The organization |
| Have I Been Pwned: Prosper data breach impacts 17.6 million accountsbleepingcomputer.com · News | News |
| Prosper Marketplace Form 8-K Item 8.01sec.gov · SEC filing | SEC filing |
Notices filed
| Where | Filed | People |
|---|---|---|
| Researchtotal | Sep 17, 2025 | |
| Have I Been Pwnedaccounts in the data | Oct 16, 2025 | 17,605,276 |
Other breaches at Prosper
| Breach | Affected | ||||
|---|---|---|---|---|---|
| Disclosed Nov 26, 2018Nov 26, 20187 years ago | Nov 26, 20187 years ago | Not stated | Finance | Confirmed | 3,115 |
History of this record
- 2026-09-25 · source_type: aggregator to filing · seed source
- 2026-09-25 · source_url: https://haveibeenpwned.com/Breach/Prosper to https://www.sec.gov/Archives/edgar/data/1416265/000141626525000038/prosper-20250901.htm · seed source
- 2026-09-25 · country: empty to US · seed source
- 2026-09-25 · sector: tech to finance · seed source
- 2026-09-25 · attack: unknown to hacking · seed source
- 2026-09-25 · data_types: ["financial","dob","emails","employment","government-id","ip-addresses","names","addresses"] to ["financial","dob","emails","employment","government-id","ip-addresses","names","addresses","ssn","other"] · seed source
- 2026-09-25 · disclosed: 2025-10-16 to 2025-09-17 · seed source
- 2026-09-25 · discovered: empty to 2025-09-01 · seed source
- 2026-09-25 · summary: In September 2025, Prosper announced that it had detected unauthorised access to their systems, which resulted in the exposure of customer and applicant information . The data breach impacted 17.6M unique email addresses, along with other c to Prosper told the SEC it identified unauthorized access to systems containing confidential information on September 1, 2025; attackers queried customer and applicant databases and took data including SSNs. Have I Been Pwned said 17.6 million · seed source
- 2026-09-25 · title: empty to Hackers steal data of 17.6 million Prosper accounts including SSNs · seed source
- 2026-09-25 · added · backfill source
First seen 2026-09-25 (Have I Been Pwned), confirmed by Company page. Record counts are as reported. Not legal advice.