Nansen alerts users to security breach involving vendor

Some Nansen users had their email addresses, password hashes and blockchain addresses exposed in a recent third-party security breach

article-image

Nansen’s Alex Svanevik | Source: Ian Walton for Blockworks

share

Blockchain data analytics platform Nansen recently suffered a security incident that exposed some users’ email addresses and passwords.

The breach appears to have originated from a third-party vendor whose system was compromised, allowing an attacker to obtain admin rights to an account used for granting customer access to Nansen.

Nansen CEO Alex Svanevik stated that the company became aware of the attack on Sept. 20. Initial investigations indicate that about 6.8% of its users are affected by the breach.

“These users had their email addresses exposed, a smaller portion also had password hashes exposed, and a last, smallest group also had their blockchain address exposed,” Svanevik said in an X post on Friday.

“We have informed our users via email if and how they’ve been affected,” he added.

Loading Tweet..

A Nansen spokesperson declined to disclose the name of the vendor, but said it has asked them to communicate on the incident publicly in case others are affected.

Nansen contacted affected users via emails sent from its official [email protected] email address on Sept. 21 between 5 pm and 9 pm UTC, instructing them to reset their passwords.

The team also informed users that while their passwords are not stored in plaintext, malicious attackers could still attempt to gain access to accounts using the compromised password and email address.

Data breaches have become increasingly frequent in the industry of late.

NFT platform OpenSea told users about a data breach in June last year when staff discovered that email addresses had been shared with an external party.

Last month, ConsenSys disclosed that about 7,000 MetaMask users had their private information, including email addresses, compromised between Aug. 2021 and Feb. 2023.

Also in August, embattled crypto companies BlockFi and FTX also reported being indirectly impacted by a cybersecurity breach related to third-party claims administration platform Kroll.


Get the news in your inbox. Explore Blockworks newsletters:

Tags

Decoding crypto and the markets. Daily, with Byron Gilliam.

Upcoming Events

Old Billingsgate

Mon - Wed, October 13 - 15, 2025

Blockworks’ Digital Asset Summit (DAS) will feature conversations between the builders, allocators, and legislators who will shape the trajectory of the digital asset ecosystem in the US and abroad.

Industry City | Brooklyn, NY

TUES - THURS, JUNE 24 - 26, 2025

Permissionless IV serves as the definitive gathering for crypto’s technical founders, developers, and builders to come together and create the future.If you’re ready to shape the future of crypto, Permissionless IV is where it happens.

Brooklyn, NY

SUN - MON, JUN. 22 - 23, 2025

Blockworks and Cracked Labs are teaming up for the third installment of the Permissionless Hackathon, happening June 22–23, 2025 in Brooklyn, NY. This is a 36-hour IRL builder sprint where developers, designers, and creatives ship real projects solving real problems across […]

recent research

Research Report Templates.png

Research

Maple Finance has successfully navigated significant market challenges through its strategic pivot to secured lending (Maple v2) and the launch of its Syrup product. Syrup has become a primary growth driver, delivering sustainable, outperforming stablecoin yields and rapidly increasing TVL. The upcoming custody-first Bitcoin staking product (istBTC) presents another significant avenue for expansion. Crucially, Maple has achieved operational profitability, a key inflection point that, combined with a fully vested token and active buyback mechanism, strengthens its investment case. While valuation metrics suggest potential undervaluation relative to peers and growth, the primary forward-looking risk identified is the long-term sustainability of its current high-take-rate collateral staking revenue model.

article-image

LBTC and sBTC integrations unlock new DeFi yields for BTC holders

article-image

The Breakdown becomes your central hub for insightful, daily crypto macro analysis

article-image

What was a cool $500,000 would now be worth more than $7 million

article-image

Mersinger’s final day at the CFTC will be May 30

article-image

Squads CEO Stepan Simkin explained why the firm launched Altitude and how he’s thinking about stablecoins

article-image

Sponsored

Instead of endless wallet popups, users could connect once, set clear rules, and delegate permission to an app or to an AI agent.