Reported by 12 outlets

Timeline

1. original reporting

   GreyNoise: Agents Gone Wild: An AI-Orchestrated Global Campaign Against PaperCut NG/MF On 31 August 2026, a likely Russian-speaking maliciou

   www.greynoise.io · 34d ago · September 9th, 2026

   GreyNoise: Agents Gone Wild: An AI-Orchestrated Global Campaign Against PaperCut NG/MF On 31 August 2026, a likely Russian-speaking maliciou

   via Mastodon https://www.greynoise.io/blog/ai-orchestrated-campaign-against-papercut-ng-mf

2. update from bleepingcomputer.com

   PaperCut warns of NG, MF flaw exploited in zero-day attacks

   bleepingcomputer.com · 47d ago · August 27th, 2026

   PaperCut is warning that hackers are actively exploiting a vulnerability in all versions of its PaperCut NG and PaperCut MF print management software in zero-day attacks. The company says it is aware of confirmed attacks on customers and is urging organizations with Internet-exposed PaperCut Application Servers to immediately restrict access to the web interfaces to trusted IP addresses. "PaperCut Software security response team is investigating active exploitation of a vulnerability affecting PaperCut NG and PaperCut MF," reads an urgent security advisory published Thursday. "We are aware of confirmed customer incidents and are treating this matter with the highest priority." PaperCut says the vulnerability affects all versions of PaperCut NG and MF, but has not shared details about the flaw or how it is being exploited. The company says its security team reproduced the vulnerability using information provided by a University customer. PaperCut has now released emergency patches for customers with public-facing PaperCut NG/MF servers. "This is an emergency patch for customers with public-facing PaperCut NG/MF servers who are unable to take other mitigating action," reads the advisory. The company continues to warn customers whose Application Servers are exposed to the Internet to use firewall rules or network access controls to restrict their web interfaces to trusted IP addresses. PaperCut also shared indicators of compromise that could indicate whether a server has been co

3. update from gbhackers.com

   PaperCut Warns of Actively Exploited Vulnerability Affecting NG and MF Servers

   gbhackers.com · 46d ago · August 28th, 2026

   Organizations with Application Servers exposed to the internet are urged to immediately restrict web access to trusted internal IP addresses and deploy emergency updates for versions 25 and […] The post PaperCut Warns of Actively Exploited Vulnerability Affecting NG and MF Servers appeared first on GBHackers Security | #1 Globally Trusted Cyber Security News Platform .

4. update from cyberpress.org

   PaperCut NG/MF Vulnerability Exploited in Active Attacks

   cyberpress.org · 46d ago · August 28th, 2026

   The company said it has received reports of customer incidents and is treating the issue as a high-priority security emergency. Although PaperCut has not yet publicly disclosed full technical details of the flaw, its incident response team said it reproduced the vulnerability using information provided by a university customer, its security team, and a digital forensics and incident response provider. The vendor stressed that administrators should take this step even when they have not identified suspicious activity. Public-facing PaperCut infrastructure should be considered particularly exposed until access controls are applied and emergency updates have been deployed. AEST on August 28. The builds are intended for customers with externally accessible PaperCut deployments that cannot promptly apply alternative mitigations. For PaperCut MF, the emergency releases are version 26.0.4.76494 and version 25.0.12.76496.

5. mentioned by securityweek.com

   PaperCut Releases Emergency Patch for Exploited Zero-Day

   securityweek.com · 46d ago · August 28th, 2026

6. update from rapid7.com

   PaperCut NG/MF Critical Zero-Day Exploited in the Wild

   rapid7.com · 46d ago · August 28th, 2026

   At the initial time of disclosure, the vulnerability had not been assigned a CVE identifier, and PaperCut had not publicly disclosed a CVSS score, vulnerability class, authentication requirements, or the technical details of the exploit path. However on August 28, the vendor assigned CVE-2026-81578 and CVE-2026-82078 for the two vulnerabilities that make up the exploit chain. CVE ID Description CWE CVSSv4 CVE-2026-81578 Authentication Bypass CWE-306 Missing authentication for critical function. 8.8 (High) CVE-2026-82078 Unsafe Dynamic Class Loading in Database Connector CWE-470 Use of Externally-Controlled input to select classes or code ('unsafe reflection'). 9.4 (Critical) PaperCut NG and PaperCut MF are print management platforms commonly deployed within enterprise, education, and other organizational environments. Because the PaperCut Application Server provides web-accessible administrative and application functionality, organizations with servers exposed to the public internet should prioritize remediation and access restriction.

7. update from malware.news

   PaperCut security advisory (AV26-858)

   malware.news · 46d ago · August 28th, 2026

   Serial number: AV26-858 Date: August 28, 2026 As of August 27, 2026, PaperCut is affected by vulnerabilities in the following products: PaperCut MF Prior to v24 Emergency Patch Release 2 Prior to v25 Emergency Patch Release 2 Prior to v26 Emergency Patch Release 2 PaperCut NG Prior to v24 Emergency Patch Release 2 Prior to v25 Emergency Patch Release 2 Prior to v26 Emergency Patch Release 2 The Cyber Centre encourages users and administrators to review the provided web link and apply any necessary updates as they become available.

8. update from bleepingcomputer.com

   PaperCut releases second emergency patch for exploited flaws

   bleepingcomputer.com · 46d ago · August 28th, 2026

   PaperCut has released a second emergency security update for two actively exploited vulnerabilities in its PaperCut NG and MF print management software after researchers discovered multiple ways to bypass the initial fixes. These vulnerabilities can be chained to bypass authentication and execute code on vulnerable servers. "Under specific conditions, unauthenticated remote requests targeting administrative functions can trigger backend actions prior to the completion of access validation checks," explains PaperCut's updated advisory . The application loads database driver classes based

9. mentioned by securityweek.com

   More Details Emerge on Exploited PaperCut Vulnerabilities

   securityweek.com · 43d ago · August 31st, 2026

10. update from gbhackers.com

    Metasploit Adds Exploit for PaperCut MF/NG Zero-Day RCE Vulnerabilities

    gbhackers.com · 43d ago · August 31st, 2026

    Rapid7’s Metasploit Framework is set to add an exploit module targeting the actively exploited chain of vulnerabilities affecting PaperCut MF and PaperCut NG. This addition will provide public offensive tooling for a security emergency involving print management servers.

11. update from cyberpress.org

    Metasploit Exploit Targets Actively Exploited PaperCut NG/MF Zero-Day RCE Chain

    cyberpress.org · 43d ago · August 31st, 2026

    Rapid7 contributor Stephen Fewer submitted pull request #21842 for CVE-2026-81578 and CVE-2026-82078, flaws that combine authentication bypass with remote code execution. The development arrives days after PaperCut confirmed customer incidents. Every PaperCut NG and MF version may be affected. Metasploit Exploit Targets Actively Exploited Emergency Patch Release 2 is available for supported 24.x, 25.x, and 26.x releases, and administrators who deployed the first emergency patch must install it because it adds protections beyond the original fix. CVE-2026-81578 is an improper-access-control issue , rated 8.8 under CVSS v4, that allows unauthenticated remote requests to invoke administrative backend actions before access validation completes. Together, they allow an unauthenticated attacker to alter configuration and abuse an external lookup path to achieve code execution in the PaperCut server process. Sfewer stated that the initial access primitive was Apache Tapestry’s “complex direct” request behavior. A request can identify one page for display while invoking a component associated with another page; PaperCut validated access to the displayed page rather than to the invoked administrative component. The chain then reconfigures exte

12. update from gbhackers.com

    CISA Flags Multiple PaperCut NG/MF Flaws Exploited in the Wild

    gbhackers.com · 43d ago · September 1st, 2026

    Cybersecurity and Infrastructure Security Agency (CISA) has added two critical vulnerabilities related to PaperCut NG/MF to its Known Exploited Vulnerabilities (KEV) catalog, warning that these flaws are being actively exploited.

13. update from cyberpress.org

    CISA Warns of Two PaperCut NG/MF Vulnerabilities Actively Exploited in Attacks

    cyberpress.org · 43d ago · September 1st, 2026

    The agency listed CVE-2026-81578 and CVE-2026-82078 on August 31, 2026, and directed affected federal civilian agencies to apply vendor mitigations by September 14 under Binding Operational Directive 26-04. An unauthenticated remote attacker can use it to modify certain system configurations, a powerful foothold when an exposed application is reachable from the internet. On its own, configuration manipulation can undermine expected administrative controls; in a chained attack, it may prepare the application or its settings for the second vulnerability. It enables an attacker to manipulate system configuration parameters and execute arbitrary Java bytecode already present on the application classpath. Crucially, that code

14. update from securityweek.com

    PaperCut Exploitation Escalates to Active Intrusions

    securityweek.com · 42d ago · September 1st, 2026

    Attacks exploiting two recently discovered PaperCut NG/MF vulnerabilities have escalated, with threat actors shifting from reconnaissance to hands-on-keyboard activity. The vendor quickly rolled out two emergency patches — one after the first was bypassed — and is working on an official release that addresses both vulnerabilities. In the meantime, attacks are escalating, according to exposure management firm WatchTowr, whose researchers have been monitoring the situation. “Activity has significantly evolved, and it did so quickly — we are no longer seeing purely exploratory probes to identify vulnerable systems, but real-world exploitation accompanied with hands-on-keyboard interaction from human attackers exploring systems they’ve compromised,” Jake Knott, head of threat intelligence at WatchTowr, said via email. “As part of this activity, it’s noteworthy that this appears to be ‘above average’ (the bar still being very low) in terms of sophistication — some designed purely to facilitate external to

15. update from bleepingcomputer.com

    Recently patched PaperCut zero-days used in data theft attacks

    bleepingcomputer.com · 42d ago · September 1st, 2026

    According to PaperCut Software, the software is used by 100 million users across more than 70,000 organizations, including large companies, state agencies, and educational institutions. PaperCut Software released two sets of emergency patches to address the vulnerabilities on Thursday and Friday , and published indicators of compromise to help defenders block ongoing attacks. Over the weekend, threat intelligence company Defused also confirmed that attackers have begun abusing the two flaws in the wild to steal data from victims' servers. "We are observing CVE-2026-81578 / CVE-2026-82078 (PaperCut NG/MF) exploit activity in our honeypots since late yesterday UTC (Aug 29th)," Defused said . "An actor is abusing the auth bypass to hijack PaperCut's external user-lookup. Unlike the RCE path in public writeups, the actor goes for data theft - dumping DB tables via Derby." Internet security watchdog Shadowserver currently tracks over 800 PaperCut MF and NG servers exposed o

16. update from socprime.com

    CVE-2026-81578: Exploited PaperCut Authentication Bypass Chains to Pre-Auth RCE

    socprime.com · 41d ago · September 2nd, 2026

    Rated 8.8 on the CVSS v4.0 scale, the vulnerability exists in the web management interface and results from administrative actions being processed before access validation has fully completed. The latest emergency update superse

17. update from cyberpress.org

    Hackers Exploit PaperCut NG/MF Flaws to Steal Credentials and Deploy Meterpreter

    cyberpress.org · 36d ago · September 7th, 2026

    Researchers Jens Pose and Ross Phillips observed attacks targeting PaperCut instances vulnerable to CVE-2026-81578 and CVE-2026-82078. Hackers Exploit PaperCut NG/MF Flaws The observed intrusion chain begins with exploitation of exposed PaperCut servers, enabling attackers to run operating-system commands through the affected application. Researchers identified basic environment-discovery commands including uname , whoami , ver , and tasklist , suggesting operators were profiling compromised machines before expanding their access. Attackers also attempted to create a privileged local account named Administrator17 , a behavior that could provide persistence and administrative control even after the initial PaperCut vulnerability is remediated. Inbound requests from 45[.]142[.]193[.]132 targeted files matching /custom/pcp_.txt and /custom/web/pcp_.txt . These files appeared to contain command output and harvested host or user information, allowing attackers to retrieve collected data from compromised PaperCut systems. The campaign involved se

18. mentioned by gbhackers.com

    Hackers Exploit PaperCut NG/MF Flaws to Steal Credentials and Deploy Meterpreter

    gbhackers.com · 36d ago · September 7th, 2026

19. mentioned by www.greynoise.io

    Hackers Use Hundreds of AI Agents to Exploit PaperCut Flaws and Compromise 440 Servers Worldwide Indicators extracted from public reporting.

    www.greynoise.io · 34d ago · September 9th, 2026

20. update from thecybersecguru.com

    A reported AI-driven campaign targeting PaperCut NG/MF has compromised 440 servers across 395 organizations in 48 countries. The campaign re

    thecybersecguru.com · 34d ago · September 9th, 2026

    A reported AI-driven campaign targeting PaperCut NG/MF has compromised 440 servers across 395 organizations in 48 countries.

21. update from www.greynoise.io

    Which is to say, a real person directed this nonsense. "On 31 August 2026, a likely Russian-speaking malicious cyber actor (MCA) used 45.142

    www.greynoise.io · 34d ago · September 9th, 2026

    Which is to say, a real person directed this nonsense.

22. mentioned by gbhackers.com

    Hackers Deploy Hundreds of AI Agents to Compromise 440 PaperCut Servers

    gbhackers.com · 33d ago · September 10th, 2026

23. update from cyberpress.org

    Hackers Deploy Hundreds of AI Agents to Exploit PaperCut Flaws and Compromise 440 Servers

    cyberpress.org · 33d ago · September 10th, 2026

    The campaign, tracked from August 31, 2026, demonstrates how large language model-powered automation can accelerate attack operations from reconnaissance through Active Directory compromise. GreyNoise said the actor moved from an empty operational workspace to remote code execution against a live victim in under four hours, then obtained its first domain administrator privileges roughly two hours later. PaperCut NG and MF are self-hosted Java print-management applications frequently integrated with Active Directory. On Windows deployments, the software commonly runs with SYSTEM-level privileges, making a successful compromise a potentially high-impact foothold into enterprise networks. GreyNoise observed the threat actor using an OpenAI Codex-based harness, a DeepSeek model, and public offensive-security tools to build, test, and execute attacks in parallel. The operators reportedly built a local test environment containing vulnerable PaperCut software and an Active Directory server, while simultaneously generating target lists through Netlas.io. Once the attack chain

24. mentioned by watchtowr.com

    @watchtowrcyber Intel captured real, hands-on-keyboard exploitation of the recent PaperCut NG/MF vulnerabilities, including fully decrypting

    watchtowr.com · 33d ago · September 10th, 2026

25. update from bleepingcomputer.com

    AI-powered attack exploited PaperCut flaws to hack 395 organizations

    bleepingcomputer.com · 33d ago · September 10th, 2026

    Most of the victims were in the education sector, accounting for roughly half of all breaches. The United States was the most targeted country, followed by the United Kingdom, France, Spain, and Canada. According to GreyNoise, the threat actor specified a list of countries to avoid, including Russia, China, Iran, Ukraine, Belarus, Moldova, Brazil, and South Africa. GreyNoise underlines that AI enables attackers to launch rapid attacks that leave defenders with very tight response

26. mentioned by www.bleepingcomputer.com

    AI-powered attack exploited PaperCut flaws to hack 395 organizations https:// bleepingcomputer.com/news/security/ ai-powered-attack-exploite

    www.bleepingcomputer.com · 33d ago · September 10th, 2026

27. mentioned by dashboard.shadowserver.org

    We shared a one-off share of over 400 compromised PaperCut NG/MF instances (via CVE-2026-81578/CVE-2026-82078) observed by @GreyNoiseIO . IP

    dashboard.shadowserver.org · 31d ago · September 12th, 2026

28. mentioned by www.bleepingcomputer.com

    # AI -powered attack exploited # PaperCut flaws to hack 395 organizations https://www. bleepingcomputer.com/news/secu rity/ai-powered-attack

    www.bleepingcomputer.com · 31d ago · September 12th, 2026

29. mentioned by www.urbanmind.net

    Reading a 1.2 Million PaperCut Fingerprint Count Correctly PaperCut NG and MF are print management platforms deployed on internal networks i

    www.urbanmind.net · 24d ago · September 19th, 2026

30. update from cyberpress.org

    PaperCut Zero-Days Exploited to Deploy AdaptixC2 and Compromise Active Directory

    cyberpress.org · 13d ago · September 30th, 2026

    Investigators found SQL statements containing large hexadecimal blobs in PaperCut’s server.log file. The blobs began with CAFEBABE, the signature associated with compiled Java classes. A first-stage loader assembled payload chunks and loaded the resulting Java bytecode directly into memory. Attack chain overview (Source: esentire) It then triggered a second-stage web shell and deleted temporary files to reduce evidence. The web shell accepted commands through the X-Quad HTTP header . Its capabilities included reading configuration values, running JavaScript, executing operating system commands

31. mentioned by gbhackers.com

    Attackers Use PaperCut RCE Chain to Steal Tokens and Access Domain Controller

    gbhackers.com · 13d ago · September 30th, 2026