Social media service Timehop publicly disclosed on July 8 that it was the victim of a data breach that impacts 21 million users.
The breach was discovered by Timehop on July 4, though an investigation by the company revealed that attackers first gained unauthorized access to the system in December 2017. Timehop reported that names, email addresses and some phone number were stolen in the breach, though the company emphasized that attackers did not directly access or manipulate users' social media accounts.
"On July 4, 2018, Timehop experienced a network intrusion that led to a breach of some of your data," Timehop wrote in an advisory. "We learned of the breach while it was still in progress, and were able to interrupt it, but data was taken."
The Timehop service enables users to be reminded of past events from their social media timelines. The service connects to users' Twitter, Instagram and Facebook accounts to source pictures and create what the firm refers to as "memories" of milestones from user posts. While Timehop has stated that user memories were not accessed, the company admitted that API keys that enable Timehop to read and show users' social media posts were also compromised.
"We have deactivated these keys so they can no longer be used by anyone—so you'll have to re-authenticate to our App," the company stated.
In a technical report detailing the security breach, Timehop stated that the attacker initially gained access to a Timehop administrator's cloud credentials in December 2017. The attacker then proceeded to create a new administrative account and conducted what Timehop referred to as reconnaissance of the Timehop's cloud deployment.
"On July 4, 2018, the attacker(s) conducted activities including an attack against the production database, and transfer of data.," Timehop stated. "At 2:43 pm US Eastern Time the attacker conducted a specific action that triggered an alarm, and Timehop engineers began to investigate. By 4:23 PM, Timehop engineers had begun to implement security measures to restore services and lock down the environment."
Part of locking down the environment for Timehop involved changing all passwords and API authentication keys. Additionally, Timehop added multifactor authentication to all of its administrative accounts that didn't already have that capability enabled. Going a step further, Timehop stated that it revoked inappropriate permissions and increased the monitoring of its deployment and product infrastructure.
Timehop was able to block the actual attack 2 hours and 19 minutes after the attackers began to remove data. In the modern world with high-speed internet connectivity, that's a lot of time for an attacker to be downloading data.
What's worse, though, is that Timehop had an unauthorized administrative user in its system for at least seven months who wasn't detected. Clearly the attacker waited for an opportune time to remove data, choosing a holiday period, likely with the expectation that they would remain undetected.
The Timehop breach clearly demonstrates that attackers don't always move rapidly to steal data and there is a certain amount of dwell time that attackers will use to surveil a system. The Timehop incident also once again demonstrates the primary importance of securing and monitoring privileged account access. The week prior to the Timehop breach, the Gentoo Linux distribution reported that one of its administrative users had been breached, leading to an attacker placing malware in the organization's GitHub repository.
Attackers generally have to execute multiple steps to be able to exfiltrate data from an organization. Having layers of security that can identify and block the different steps in an attack chain is key to limiting risk.
Sean Michael Kerner is a senior editor at eWEEK and InternetNews.com. Follow him on Twitter @TechJournalist.