Check Point Research has uncovered a new wave of Operation Dream Job, the long-running North Korean campaign that lures defense and aerospace professionals with convincing fake job offers. This iteration is more dangerous than previous versions: it includes a previously unknown Windows vulnerability now patched as CVE-2026-68820, a newly documented backdoor called Troy, and command infrastructure built almost entirely from legitimate servers the attackers didn’t build, they hijacked them. Targets confirmed in France, Germany, Brazil, and India.
“The attackers used a previously unknown vulnerability in Windows (CVE-2026-68820) to gain full control of infected computers and evade EDR visibility. Check Point reported the issue to Microsoft, which released a fix before this research was published” reads the report published by Check Point Research. “Rather than running their own servers, the attackers are hijacking legitimate but compromised websites and webmail servers to relay commands, making the malicious traffic harder to distinguish from normal activity”
The vulnerability, CVE-2026-68820, is the same actively exploited zero-day that Microsoft patched on August 11 as part of Patch Tuesday, a privilege escalation flaw in AFD.sys, the kernel driver underlying Windows Sockets. Check Point reported the issue to Microsoft on July 28, Microsoft confirmed it three days later, and the fix shipped two weeks after that. The zero-day in this campaign and the zero-day under active exploitation are the same bug.
The attack runs through two parallel infection chains. In the first, victims download an encrypted archive containing a legitimate signed PDF viewer and a malicious DLL. The DLL displays a convincing Lockheed Martin job description while silently loading MISTPEN, a lightweight downloader that communicates through Microsoft Graph API and OneDrive. MISTPEN then runs reconnaissance modules, triggers the AFD.sys exploit to achieve SYSTEM privileges, and deploys ForestTiger, a well-documented Lazarus backdoor, along with an updated version of the group’s kernel-mode rootkit, FudModule 3.1, which can now tamper with Windows Smart App Control to bypass software verification.
“The second chain is more recent and shares several characteristics with a campaign described by ESET against the UAV sector in 2025. Victims are instructed to download SecurityPDF, a trojanized PDF viewer, from one of several websites impersonating Enveil, a legitimate privacy technology company with no actual connection to the attack. Once installed, the modified viewer inspects any PDF opened through it for a hidden marker.” continues the report. “When the marker is present, the application decrypts and launches an embedded payload that loads the Troy backdoor directly into memory.”
Troy is a single DLL implant that supports 17 operator commands covering file operations, shell access, process termination, in-memory DLL injection, and configuration updates. Its name comes from a PDB path embedded in the binary that Check Point also observed in earlier Lazarus samples. Enveil has no connection to the campaign; its brand was simply borrowed because it sounds credible to defense sector professionals.
The C2 infrastructure is built from compromised Roundcube webmail installations and WordPress sites, many vulnerable to CVE-2025-49113, infected with a previously undocumented PHP webshell called RelayShell. RelayShell functions as a relay rather than a traditional backdoor, exchanging commands and responses through simple text files. In at least one confirmed case, an already-breached French organization was used to send phishing messages to new victims — the attackers borrowed the company’s reputation to get past filters. Check Point identified at least 17 unique server identifiers in this relay network, with operators connecting through commercial VPNs to further obscure their location.
The most urgent action is applying the August 2026 Patch Tuesday update, which contains the CVE-2026-68820 fix. For organizations running public-facing Roundcube or CMS installations, the secondary risk is becoming part of the relay infrastructure rather than the intended target: the servers used in this campaign were compromised through leaked credentials and a known unpatched vulnerability, not anything exotic. The full indicators of compromise are in Check Point’s report.
“Given the combination of a zero day vulnerability that now have a patch, a new modular backdoor, and web based infrastructure designed to resemble legitimate traffic, security teams in these sectors should prioritize the August Patch Tuesday update, review the indicators of compromise published in Check Point Research publication, and apply the same level of scrutiny to unsolicited recruiting outreach that they would apply to any unverified download request.” concludes the report.
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