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Hackers Deploy Hundreds of AI Agents to Compromise 440 PaperCut Servers

AI-agent campaign exploited PaperCut CVE-2026-81578 and CVE-2026-82078, compromising 440 servers at 395 organizations and reaching Domain Admin in 12.

GreyNoise tracked a likely Russian-speaking actor that used AI agents (OpenAI Codex, a DeepSeek model) to exploit an authentication bypass (CVE-2026-81578) and unsafe-reflection RCE (CVE-2026-82078) in PaperCut NG/MF starting August 31, 2026. At least 440 servers across 395 organizations in 48 countries were compromised, with one US high school going from initial access to Domain Admin in seven minutes. Escalation relied on LSASS and registry credential harvesting, pass-the-hash, the noPac technique (CVE-2021-42278/CVE-2021-42287), new Domain Admin accounts, and DCSync to steal NTDS.DIT data. Operators staged registry hives, used Ligolo tunneling and certutil Base64 encoding for exfiltration, and one attempt was blocked by Cloudflare WAF.

GBHackersupdated · 5d agofirst · 6d agoExploit / PoC in the wild 7 sourcesCVE-2026-81578CVE-2026-82078CVE-2021-42278+1 CVEs1

Adobe Commerce Zero-Day Exploited to Backdoor Online Stores

Sansec found attackers exploiting an Adobe Commerce/Magento zero-day (StyleSmuggler) since September 4 to deploy Rust backdoors on online stores.

Threat actors are actively exploiting a zero-day RCE in Adobe Commerce and Magento 2.4.7-2.4.9, injecting PHP code via generated failure reports and executing it through Magento's payment-failure email, with no user interaction required. Exploitation began September 4 and succeeds even against stores running the July and August 2026 patches; the Rust backdoor disguises itself as kworker/u:8:0 or fc-cache and hides C&C communication inside fake NTP replies. Adobe's September 8 Patch Tuesday updates may not include a StyleSmuggler fix.

SecurityWeek · 9d agoExploit / PoC in the wild

Active exploitation of Cisco Secure Firewall Management Center vulnerabilities

Cisco Talos reports in-the-wild exploitation of critical FMC flaw CVE-2026-20079 by three clusters including a Sandworm-linked APT and Qilin ransomware affiliates.

Cisco Talos is tracking active exploitation of CVE-2026-20079 (CVSS 10.0), an authentication bypass in Cisco Secure Firewall Management Center that lets unauthenticated remote attackers execute scripts and obtain root access, and CVE-2026-20316 (CVSS 5.3), which permits low-privileged logins and can be chained for privilege escalation. Talos identified three post-compromise clusters: UAT-12197 deploying JSP web shells and a JAR command executor for credential theft; UAT-11823, an APT overlapping with Sandworm, deploying a Netcat reverse shell and Cyclops Blink malware; and UAT-11988, assessed as a ransomware operator with TTPs consistent with Qilin affiliates. Hotfixes are available, with a comprehensive hardening release due the week of September 14, 2026.

Rogue ScreenConnect Installations Across Unrelated Hosts Suggest Worm-Like Activity

Huntress observed rogue ScreenConnect deployments with worm-like VBScript propagation across unrelated organizations, prompting a ConnectWise advisory on file transfer behavior.

Huntress identified multiple incidents in late August 2026 where social engineering led to rogue ScreenConnect remote access clients deployed on victim machines, which then spawned wscript.exe to run four VBScript payloads (1.vbs through 4.vbs) for profiling, telemetry collection, and persistence via a WindowsServiceHost Run key. Modified ScreenConnect clients propagated the VBScript chain to connected endpoints, creating worm-like spread. ConnectWise published an advisory on September 3, 2026, confirming an issue affecting file transfer behavior in both cloud and on-premises ScreenConnect deployments, with a CVE and fix expected within the week; partners were advised to review and disable TransferFiles permissions in the interim.

Huntress · 13d agoExploit / PoC in the wild1

Chinese Hackers Exploit Critical Tencent Software Flaw for One-Click Code Execution

China-linked UNC3569 actively exploited critical Sogou Input Method flaw CVE-2026-51990 for one-click system-level code execution, deploying the GrayRabbit backdoor.

Gen Threat Labs reports that China-linked threat actor UNC3569, possibly tied to contractor i-SOON, exploited critical CVE-2026-51990 in Tencent's Sogou Input Method, a Windows IME used by hundreds of millions, via crafted sgbiz URLs. The chain combines unvalidated command-line argument injection, unrestricted URL navigation, and an un-sandboxed Chromium 80 engine missing roughly six years of security patches. The exploit gives system-level code execution and was used to deploy the GrayRabbit backdoor, which provides a reverse shell, plugin loading, file upload to C2, and system info collection, and has appeared in UNC3569 intrusions since at least 2021. Tencent patched the issue in version 16.3.0.3498 via automatic update, but the outdated Chromium configuration reportedly remained unchanged as of September 10.

SecurityWeek · 2d agoExploit / PoC in the wild 2 sourcesCVE-2026-519901· 1 read

Novel Blue Moon kit targeting Chrome and Windows reflects new reality of AI-driven exploits

Proofpoint reports the BlueMoon exploit kit, chaining two Chrome V8 zero-days and a Windows ALPC bug, being shared across China-linked espionage groups.

Proofpoint identified a new exploit kit, BlueMoon, first observed on August 28 and used by TA412 (APT31/Violet Typhoon) against US NGOs, mining firms, and commodity trading companies. The kit chains a V8 type confusion RCE (CVE-2026-85046), a V8 sandbox escape, and a Windows Advanced Local Procedure Call privilege escalation (CVE-2026-85880), both patched flaws having been exploited in the wild. At least four espionage groups, most with suspected China nexus including UNK_LateNight, adopted the kit within days, targeting US aerospace firms with defense-sector lures. Fewer than 20 organizations were observed targeted, and researchers believe AI-assisted exploit development against upstream Chromium patches enabled the kit's rapid creation and sharing.

The Register · Securityupdated · 5h agofirst · 6d agoExploit / PoC in the wild 16 sourcesCVE-2026-85046CVE-2026-858801

Critical N-able N-central Vulnerability and Active Exploitation

N-able N-central pre-auth RCE zero-day CVE-2026-86218 (CVSS 10.0) is exploited in the wild; on-prem admins must upgrade to 2026.3 HF4.

N-able disclosed a third N-central vulnerability, CVE-2026-86218, a pre-authentication RCE rated CVSS 10.0, and released hotfix 2026.3 HF4 superseding build 2026.3.1.13. Huntress reproduced an exploit chain involving an authentication bypass (CVE-2026-86206/CVE-2026-86207) after a fully patched customer's N-central production server was compromised on September 4. Attackers appended strings like .invalid to account names and probed the /remoteControlAction.do?method=getPierDetails endpoint; Huntress worked with Cloudflare to disable adversary tunnel infrastructure. Hosted N-central instances are already patched; on-prem administrators must upgrade immediately.

Huntress · 10d agoExploit / PoC in the wildCVE-2026-86218CVE-2026-86206CVE-2026-86207+2 CVEs

StyleSmuggler: Magento and Adobe Commerce 0-day RCE (CVE-2026-75650) under active attack

Sansec details actively exploited StyleSmuggler 0-day (CVE-2026-75650, CVSS 10.0) unauthenticated RCE in Magento and Adobe Commerce, patched by Adobe hotfix APSB26-146.

Sansec is investigating StyleSmuggler, an actively exploited unauthenticated remote code execution chain in Magento Open Source and Adobe Commerce, now tracked as CVE-2026-75650 with CVSS 10.0. Adobe released hotfix VULN-39341 via APSB26-146 (priority 1) on September 7 for versions 2.4.4 through 2.4.9, but stores were being exploited for roughly three days before the fix existed. The implant is a Rust backdoor that disguises itself as kworker, fc-cache, or chronyd processes and exfiltrates host data in MessagePack records sent as fake NTP replies over UDP port 123. Adobe advises rotating the encryption key and every credential it protected, and Sansec stresses patching does not clean already-compromised stores.

Attackers Chain Two PaperCut Flaws to Execute Code Without Authentication

Attackers chain PaperCut NG/MF flaws CVE-2026-81578 and CVE-2026-82078 for unauthenticated RCE; exploitation observed and a second emergency patch issued.

Two flaws in PaperCut NG and MF — CVE-2026-81578 (CVSS 8.8, improper access control enabling auth bypass) and CVE-2026-82078 (CVSS 9.4, unsafe dynamic class loading) — are being chained for unauthenticated remote code execution. Huntress observed limited exploitation on two customer environments, including Base64-encoded commands, 'whoami & ver' fingerprinting, SimpleHelp execution, and AnyDesk installation for persistence. PaperCut released a second emergency patch for v24, v25, and v26, but watchTowr reports additional patch bypasses may still affect the latest version. Shared IoCs include crafted jdbc strings in server.log and attacker-written .class/.cmd files.

The Hacker News · 14d agoExploit / PoC in the wildCVE-2026-82078CVE-2026-815781

Attackers plant remote access tools on compromised PaperCut servers

Attackers chained two PaperCut NG/MF zero-days for unauthenticated access, installing SimpleHelp and AnyDesk remote access tools on compromised servers.

An ongoing campaign exploits chained zero-days CVE-2026-81578 (improper access control) and CVE-2026-82078 (unsafe dynamic class loading) in internet-facing PaperCut NG and MF Application Servers, enabling authentication bypass and arbitrary Java bytecode execution. Post-compromise activity includes user and domain enumeration, payload download from sendit.sh, and silent installation of SimpleHelp and AnyDesk for redundant remote access; Defused observed CVE-2026-81578/CVE-2026-82078 exploit activity in honeypots since August 29, including data theft via Derby database dumps. Emergency patches were released August 28 and August 30, but 47% of roughly 2,500 PaperCut installs tracked by Huntress run v23 or older, for which no patch is available.

Help Net Security · 14d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-820781