FritzFrog Botnet
FritzFrog is a crypto mining botnet with a number of sophisticated features to aid propagation and hinder detection. Since January 2020, it has infected over 500 individual organisations worldwide.
Summary
FritzFrog is a crypto mining botnet with a number of sophisticated features to aid propagation and hinder detection. Since January 2020, it has infected over 500 individual organisations worldwide.
Affected platforms
The following platforms are known to be affected:
Threat details
Introduction
First observed in January 2020, FritzFrog is an advanced peer-to-peer (P2P) botnet and worm targeting education, financial, government, healthcare, and telecommunications organisations globally.
Written in Go, it displays a number of sophisticated features, including fileless execution and a bespoke P2P protocol, that suggest it may be developed by an unknown advanced persistent threat group.
Propagation & activities
FritzFrog propagates to new systems using brute-force attacks on exposed SSH services. Interestingly, these attacks appear to be distributed across the botnet, with each FritzFrog instance making attempts in sequence to prevent detection.
If successful, it will inject a copy of itself directly into memory using the names ifconfig and nginx. The new copy then connects to the FritzFrog botnet over TCP 1234 to download the XMRig mining application before deploying it over TCP 5555. While the miner is running, FritzFrog will monitor system resources and terminate any processes that are over-utilising CPU resources.
P2P protocol
The P2P protocol used by the FritzFrog botnet appears to be entirely proprietary and allows each individual instance to act as both a bot and a controller if necessary. This decentralisation allows FritzFrog to be highly resilient.
Remediation advice
To prevent and detect an infection, NHS Digital advises that:
- Secure configurations are applied to all devices.
- Security updates are applied at the earliest opportunity.
- Tamper protection settings in security products are enabled where available.
- Obsolete platforms are segregated from the rest of the network.
- IT usage policies are reinforced by regular training to ensure all users know not to open unsolicited links or attachments.
- Multi-factor authentication (MFA) and lockout policies are used where practicable, especially for administrative accounts.
- Administrative accounts are only used for necessary purposes.
- Remote administration services use strongly encrypted protocols and only accept connections from authorised users or locations.
- Systems are continuously monitored, and unusual activity is investigated, so that a compromise of the network can be detected as early as possible.
Please note that the NCSC maintains guidance for securely configuring a wide range of end user device (EUD) platforms. For further details refer to their end user device security guidance pages.
Indicators of compromise
Last edited: 19 August 2020 3:26 pm