Canada Revenue Agency

Summary

Hackers exploited the Heartbleed vulnerability in OpenSSL to breach the Canada Revenue Agency's systems, stealing sensitive taxpayer data including approximately 900 Social Insurance Numbers and potentially business-related information during a six-hour attack window. The vulnerability allowed unauthorized access to private encryption keys, passwords, and other confidential data from servers running affected OpenSSL versions. The agency temporarily disabled online tax services following public disclosure of the flaw, but the breach occurred prior to mitigation efforts, marking one of the first confirmed malicious uses of the critical OpenSSL weakness.

Motives

Detailed motive labels are available to members.

TTPs

Detailed technique labels are available to members.

Description

In April 2014, the Canada Revenue Agency (CRA) suffered a data breach when attackers exploited the Heartbleed vulnerability in OpenSSL, a widely used cryptographic library. The vulnerability, which had existed undetected for approximately two years, allowed unauthorized access to sensitive data from servers running affected OpenSSL versions by extracting information directly from system memory. CRA officials disabled public access to online tax services on April 8, 2014 – one day after public disclosure of Heartbleed – but forensic analysis revealed attackers had already exploited the flaw during a six-hour window prior to the shutdown. Government security agencies confirmed malicious actors extracted Social Insurance Numbers (SINs) belonging to approximately 900 Canadian taxpayers during this period. The breach marked one of the first confirmed malicious exploitations of Heartbleed following its public disclosure, demonstrating the rapid weaponization of the critical vulnerability.

The attackers leveraged Heartbleed to compromise CRA systems and extract not only SINs but also fragments of business-related data, though the full scope of business impacts remained under analysis at the time of reporting. CRA initiated a detailed forensic review to identify all compromised data fragments while notifying affected individuals. The incident prompted immediate system isolation and service suspension as containment measures, with officials emphasizing the targeted exploitation occurred exclusively through the OpenSSL vulnerability. No evidence suggested broader system compromise beyond the data exfiltrated via Heartbleed during the identified six-hour attack window. The breach highlighted the operational risks posed by widespread cryptographic vulnerabilities, particularly given OpenSSL's extensive adoption across internet infrastructure.

Sources

Sources available to members: 1 source.