The National Security Agency (NSA), Cybersecurity and Infrastructure Security Agency (CISA), Federal Bureau of Investigation (FBI) and the UK’s National Cyber Security Centre (NCSC) released a Cybersecurity Advisory today exposing malicious cyber activities against the U.S. and global organisations, starting from mid-2019 and likely ongoing. This advisory is being released as part of the NSA’s routine and continuing cybersecurity mission to warn network defenders of nation-state threats.
The advisory details how another country has targeted hundreds of U.S. and foreign organisations using brute force access to penetrate government and private sector victim networks. The advisory reveals the Tactics, Techniques, and Procedures (TTPs) used in their campaign to exploit targeted networks, access credentials, move laterally, and collect and exfiltrate data. It also arms system administrators with the mitigations needed to counter this threat.
Malicious cyber actors use brute force techniques to discover valid credentials often through extensive login attempts, sometimes with previously leaked usernames and passwords or by guessing with variations of the most common passwords. While the brute force technique is not new, in this case, the cyber actors uniquely leveraged software containers to easily scale their brute force attempts.
Once valid credentials were discovered, the cyber actors combined them with various publicly known vulnerabilities to gain further access into victim networks. This, along with various techniques also detailed in the advisory, allowed the actors to evade defences and collect and exfiltrate various information in the networks, including mailboxes.
The advisory warns system administrators that exploitation is almost certainly ongoing. Targets have been global but primarily focused on the U.S. and Europe. Targets include government and military, defence contractors, energy companies, higher education, logistics companies, law firms, media companies, political consultants or political parties, and think tanks.
NSA encourages Department of Defense (DoD), National Security Systems (NSS), and Defence Industrial Base (DIB) system administrators to immediately review the indicators of the compromise included in the advisory and to apply the recommended mitigations. The most effective mitigation is the use of multi-factor authentication, which is not guessable during brute force access attempts.
As with mitigations for other credential theft techniques, organisations can take the following measures to ensure strong access control:
- Use multi-factor authentication with strong factors and require regular reauthentication. Strong authentication factors are not guessable, so they would not be guessed during brute force attempts.
- Enable time-out and lock-out features whenever password authentication is needed. Time-out features should increase in duration with additional failed login attempts. Lock-out features should temporarily disable accounts after many consecutive failed attempts. This can force slower brute force attempts, making them infeasible.
- For protocols that support human interaction, utilise captchas to hinder automated access attempts.
- Change all default credentials and disable protocols that use weak authentication (e.g., clear-text passwords, or outdated and vulnerable authentication or encryption protocols) or do not support multi-factor authentication. Always configure access controls on cloud resources carefully to ensure that only well-maintained and well-authenticated accounts have access.
- Employ appropriate network segmentation and restrictions to limit access and utilise additional attributes (such as device information, environment, access path) when making access decisions, with the desired state being a Zero Trust security model
- Use automated tools to audit access logs for security concerns and identify anomalous access requests.
- Some services can check passwords against common password dictionaries when users change passwords, denying many poor password choices before they are set. This makes brute-force password guessing far more difficult.
As part of the ongoing response, agencies across the U.S. government announced new resources and initiatives to protect American businesses and communities from ransomware attacks. As reported by OpenGov Asia, the U.S. Department of Homeland Security (DHS) and the U.S. Department of Justice (DOJ), together with federal partners, has launched a new website to combat the threat of ransomware.
StopRansomware.gov establishes a one-stop hub for ransomware resources for individuals, businesses, and other organisations. The new website is a collaborative effort across the federal government and the first joint website created to help private and public organisations mitigate their ransomware risk.
