SMTP is the key: BPFDoor and AVERAT hitting the network edge


Rapid7 tracked a set of Linux samples that blend into the software and device conventions of the telecom environments they target. The set spans a newly observed BPFDoor variant, a BPF Rekoobe build seen against South Korean targets, a dropper, and six builds of a Linux implant Rapid7 researchers track as AVERAT, deployed against Taiwanese appliances. Additionally, researchers provide source code details of the Rapid7 BPFDoor controller introduced in our April 2026 blog, Stealthy BPFDoor Variants are a Needle That Looks Like Hay.

The chain uses two binaries. A dropper writes a shell script to the appliance’s storage mount and executes it. The script stages both payloads into /sbin under the names ntpdate and udevds, launches them, and deletes each file ten seconds later while the processes continue running. One of those payloads is the dropper itself, re-executing as a resident watchdog, leaving both processes running without an on-disk image.

Read more…
Source:  Rapid7 News


Sign up for the Cyber Security Review Newsletter
The latest cyber security news and insights delivered right to your inbox


Related:

  • Tortoiseshell Group Targets IT Providers in Saudi Arabia in Probable Supply Chain Attacks

    October 18, 2019

    Previously undocumented group hits IT providers in the Middle East. A previously undocumented attack group is using both custom and off-the-shelf malware to target IT providers in Saudi Arabia in what appear to be supply chain attacks with the end goal of compromising the IT providers’ customers. The group, which we are calling Tortoiseshell, has been active ...

  • Phorpiex Botnet Shifts Gears From Ransomware to Sextortion

    October 17, 2019

    A  recent wide-scale campaign indicates that a decade-old botnet is shifting gears from distributing ransomware to delivering millions of sextortion threats to innocent recipients. Worse, researchers say that the botnet’s spam campaign can affect up to 27 million potential victims. The botnet, Phorpiex, has been active for almost a decade and currently controls almost 500,000 computers globally. The ...

  • Equipping the Education Sector With Threat Intelligence to Defend Against Cyberattacks

    October 17, 2019

    When you think about sophisticated cyberattacks, certain targeted industries probably come to mind immediately — government, critical infrastructure, and financial services, to name a few. It’s fair to say that for most people, the education sector isn’t generally first on that list. Despite this, educational institutions (particularly those in higher education) have become an increasingly popular ...

  • Cisco Aironet Access Points Plagued By Critical, High-Severity Flaws

    October 17, 2019

    Cisco Systems has released a security update stomping out critical and high-severity flaws impacting its Aironet access points, which are entry-level wireless access points (APs) used by mid-size enterprises in their offices or small warehouses. It also issued a slew of additional patches addressing other flaws in its products. The most severe of the AP bugs is ...

  • Graboid: First-Ever Cryptojacking Worm Found in Images on Docker Hub

    October 16, 2019

    Unit 42 researchers identified a new cryptojacking worm we’ve named Graboid that’s spread to more than 2,000 unsecured Docker hosts. We derived the name by paying homage to the 1990’s movie “Tremors,” since this worm behaves similarly to the sandworms in the movie, in that it moves in short bursts of speed, but overall is ...

  • APT trends report Q3 2019

    October 16, 2019

    For more than two years, the Global Research and Analysis Team (GReAT) at Kaspersky has been publishing quarterly summaries of advanced persistent threat (APT) activity. The summaries are based on our threat intelligence research and provide a representative snapshot of what we have published and discussed in greater detail in our private APT reports. They ...