Security researchers have discovered a new worm and botnet dubbed Gitpaste-12, named for its usage of GitHub and Pastebin to host component code and the 12 known vulnerabilities it exploits to compromise systems.
The Juniper Threat Labs research team detected the first Gitpaste-12 attacks on Oct. 15, 2020; however, the team notes the first commit was seen on GitHub on July 9, meaning the malware had lived on GitHub since then. Researchers reported the Pastebin URL and git repo, which was closed on Oct. 30, 2020, and should stop the spread of the botnet.
Gitpaste-12 has 12 unique attack modules available, though researchers note there is evidence its development is ongoing. Its current targets are Linux-based x86 servers, and Linux ARM and MIPS-based Internet of Things (IoT) devices.
In the first phase of an attack, Gitpaste-12 attempts to use known exploits to compromise target systems and may attempt to brute-force passwords. After the initial compromise, the malware downloads a script from Pastebin; this calls the same script and executes it again every minute, researchers explain in a blog post. This is presumably how the botnet is updated.
The main shell script uploaded to the victim's machine during the attack starts to download and execute other part of Gitpaste-12. It also downloads and executes components from GitHub.
Following this, the malware prepares its target environment by eliminating system defenses such as firewall rules and common threat prevention and monitoring software. Researchers discovered a script that contains comments written in Chinese and commands to disable some security tools. In one example, commands disable cloud security agents, indicating the attacker meant to target public cloud infrastructure provided by Alibaba Cloud and Tencent, they note.
Alex Burt, security researcher with Juniper Threat Labs, says the attack was detected from China's IP; however, "we do not know if this is just an infected host or the original attacker's own machine," he says. While other attackers use GitHub or Pastebin to store component code, Burt notes, they don't typically use both of them.
Gitpaste-12 also has the ability to mine for Monero cryptocurrency, as well as a method to spread itself across different machines.
"The Gitpaste-12 malware also contains a script that launches attacks against other machines, in an attempt to replicate and spread," researchers explain. "It chooses a random/8 CIDR for attack and will try all addresses within that range." Some compromised systems have TCP posts 30004 and 30005 open for shell commands, they add.
The botnet uses 11 vulnerabilities and a telnet brute-forcer to spread. These known flaws exist in products including Asus routers, the Netlink GPON router, AVTECH IP camera, Huawei router, Apache Struts, and Mongo DB, among others.
"This is a good collection of exploits for IoT devices," Burt says. "It appears attackers spent a lot of effort on this attack."
While the closing of the git repo should stop proliferation of Gitpaste-12, he says the operators could use other hosting or create another account on GitHub or Pastebin in order to bring the botnet back.