Command and Control | Breaking Cybersecurity News | The Hacker News

Microsoft has disclosed details of a novel backdoor dubbed SesameOp that uses OpenAI Assistants Application Programming Interface (API) for command-and-control (C2) communications. "Instead of relying on more traditional methods, the threat actor behind this backdoor abuses OpenAI as a C2 channel as a way to stealthily communicate and orchestrate malicious activities within the compromised environment," the Detection and Response Team (DART) at Microsoft Incident Response said in a technical report published Monday. "To do this, a component of the backdoor uses the OpenAI Assistants API as a storage or relay mechanism to fetch commands, which the malware then runs." The tech giant said it discovered the implant in July 2025 as part of a sophisticated security incident in which unknown threat actors had managed to maintain persistence within the target environment for several months. It did not name the impacted victim. Further investigation into the intrusio...

Cybersecurity researchers have shed light on a previously undocumented threat actor called TA585 that has been observed delivering an off-the-shelf malware called MonsterV2 via phishing campaigns. The Proofpoint Threat Research Team described the threat activity cluster as sophisticated, leveraging web injections and filtering checks as part of its attack chains. "TA585 is notable because it appears to own its entire attack chain with multiple delivery techniques," researchers Kyle Cucci, Tommy Madjar, and Selena Larson said . "Instead of leveraging other threat actors – like paying for distribution, buying access from initial access brokers, or using a third-party traffic delivery system – TA585 manages its own infrastructure, delivery, and malware installation." MonsterV2 is a remote access trojan (RAT), stealer, and loader, which Proofpoint first observed being advertised on criminal forums in February 2025. It's worth noting that MonsterV2 is also calle...

Cybersecurity researchers are calling attention to a series of cyber attacks targeting financial organizations across Africa since at least July 2023 using a mix of open-source and publicly available tools to maintain access. Palo Alto Networks Unit 42 is tracking the activity under the moniker CL-CRI-1014 , where "CL" refers to "cluster" and "CRI" stands for "criminal motivation." It's suspected that the end goal of the attacks is to obtain initial access and then sell it to other criminal actors on underground forums, making the threat actor an initial access broker (IAB). "The threat actor copies signatures from legitimate applications to forge file signatures , to disguise their toolset and mask their malicious activities," researchers Tom Fakterman and Guy Levi said . "Threat actors often spoof legitimate products for malicious purposes." The attacks are characterized by the deployment of tools like PoshC2 fo...

A new malware campaign is exploiting a weakness in Discord's invitation system to deliver an information stealer called Skuld and the AsyncRAT remote access trojan. "Attackers hijacked the links through vanity link registration, allowing them to silently redirect users from trusted sources to malicious servers," Check Point said in a technical report. "The attackers combined the ClickFix phishing technique, multi-stage loaders, and time-based evasions to stealthily deliver AsyncRAT, and a customized Skuld Stealer targeting crypto wallets." The issue with Discord's invite mechanism is that it allows attackers to hijack expired or deleted invite links and secretly redirect unsuspecting users to malicious servers under their control. This also means that a Discord invite link that was once trusted and shared on forums or social media platforms could unwittingly lead users to malicious sites. Details of the campaign come a little over a month after the ...

The Russia-linked threat actor known as Gamaredon (aka Shuckworm) has been attributed to a cyber attack targeting a foreign military mission based in Ukraine with an aim to deliver an updated version of a known malware called GammaSteel. The group targeted the military mission of a Western country, per the Symantec Threat Hunter team, with first signs of the malicious activity detected on February 26, 2025. "The initial infection vector used by the attackers appears to have been an infected removable drive," the Broadcom-owned threat intelligence division said in a report shared with The Hacker News. The attack started with the creation of a Windows Registry value under the UserAssist key, followed by launching "mshta.exe" using "explorer.exe" to initiate a multi-stage infection chain and launch two files. The first file, named "NTUSER.DAT.TMContainer00000000000000000001.regtrans-ms," is used to establish communications with a command-and...

Google is warning of multiple threat actors sharing a public proof-of-concept (PoC) exploit that leverages its Calendar service to host command-and-control (C2) infrastructure. The tool, called Google Calendar RAT (GCR) , employs Google Calendar Events for C2 using a Gmail account. It was first published to GitHub in June 2023. "The script creates a 'Covert Channel' by exploiting the event descriptions in Google Calendar," according to its developer and researcher Valerio Alessandroni, who goes by the online alias MrSaighnal. "The target will connect directly to Google." The tech giant, in its eighth Threat Horizons Report [PDF], said it has not observed the use of the tool in the wild, but noted its Mandiant threat intelligence unit has detected several threat actors sharing the PoC on underground forums. "GCR, running on a compromised machine, periodically polls the Calendar event description for new commands, executes those commands on the t...

As many as 85 command-and-control (C2) servers have been  discovered  supported by the ShadowPad malware since September 2021, with infrastructure detected as recently as October 16, 2022. That's according to VMware's Threat Analysis Unit (TAU), which  studied  three ShadowPad variants using TCP, UDP, and HTTP(S) protocols for C2 communications. ShadowPad , seen as a successor to  PlugX , is a modular malware platform privately shared among multiple Chinese state-sponsored actors since 2015. Taiwanese cybersecurity firm TeamT5, earlier this May, disclosed details of another China-nexus modular implant named  Pangolin8RAT , which is believed to be the successor of the PlugX and ShadowPad malware families, linking it to a threat group dubbed Tianwu. An analysis of the three ShadowPad artifacts, which have been previously put to use by  Winnti ,  Tonto Team , and an emerging threat cluster codenamed  Space Pirates , made it possible to di...

A nascent service called Dark Utilities has already attracted 3,000 users for its ability to provide command-and-control (C2) services with the goal of commandeering compromised systems. "It is marketed as a means to enable remote access, command execution, distributed denial-of-service (DDoS) attacks and cryptocurrency mining operations on infected systems," Cisco Talos  said  in a report shared with The Hacker News. Dark Utilities, which emerged in early 2022, is advertised as a "C2-as-a-Service" (C2aaS), offering access to infrastructure hosted on the clearnet as well as the TOR network and associated payloads with support for Windows, Linux, and Python-based implementations for a mere €9.99. Authenticated users on the platform are presented with a dashboard that makes it possible to generate new payloads tailored to a specific operating system that can then be deployed and executed on victim hosts. Additionally, users are provided an administrative panel ...