Prosper

Disclosed Sep 17, 202517,605,276 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	FinancialDates of birthEmailsEmploymentGovernment IDsIP addressesNamesAddressesSocial Security numbersOther
Sector	Finance · US
Status	Confirmed
Check your email	Have I Been Pwned

Sources

Aggregatorhaveibeenpwned.com

Have I Been Pwned: Prosper

The organizationprosper.com

Prosper disclosure

Newsbleepingcomputer.com

Have I Been Pwned: Prosper data breach impacts 17.6 million accounts

SEC filingsec.gov

Prosper Marketplace Form 8-K Item 8.01

Notices filed

TotalSep 17, 2025

ResearchCount not stated

Accounts in the dataOct 16, 2025

Have I Been Pwned17,605,276 people

Other breaches at Prosper

Breach, details not statedExposed names, Social Security numbers, government IDs, payment cards and financial details. Reported to the Maine AG.3,115 affectedFinanceUSNov 26, 2018

History of this record

source_type2026-09-25

aggregator to filingby seedSource

source_url2026-09-25

https://haveibeenpwned.com/Breach/Prosper to https://www.sec.gov/Archives/edgar/data/1416265/000141626525000038/prosper-20250901.htmby seedSource

country2026-09-25

empty to USby seedSource

sector2026-09-25

tech to financeby seedSource

attack2026-09-25

unknown to hackingby seedSource

data_types2026-09-25

["financial","dob","emails","employment","government-id","ip-addresses","names","addresses"] to ["financial","dob","emails","employment","government-id","ip-addresses","names","addresses","ssn","other"]by seedSource

disclosed2026-09-25

2025-10-16 to 2025-09-17by seedSource

discovered2026-09-25

empty to 2025-09-01by seedSource

summary2026-09-25

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 millionby seedSource

title2026-09-25

empty to Hackers steal data of 17.6 million Prosper accounts including SSNsby seedSource

Added2026-09-25

First recordedby backfillSource

First seen 2026-09-25 (Have I Been Pwned), confirmed by Company page. Record counts are as reported. Not legal advice.

Everything about Prosper