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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

PaperCut NG/MF vulnerabilities exploited in zero-day attacks

PaperCut warns of active zero-day exploitation chaining CVE-2026-81578 and CVE-2026-82078 for pre-auth remote code execution in NG/MF print management.

PaperCut Software confirmed attackers are chaining two vulnerabilities in PaperCut NG and MF: CVE-2026-81578, an improper access control flaw in the web management interface allowing unauthenticated configuration changes, and CVE-2026-82078, unsafe dynamic class loading in database connection utilities enabling arbitrary Java bytecode execution. Huntress reproduced a pre-authentication remote configuration takeover and full RCE chain against PaperCut NG 25.0.11.75758 and observed limited exploitation at two customers, including post-exploitation whoami and ver commands. The vendor released Emergency Patch Release 2 with additional hardening and urged restricting Application Server web access to trusted IPs. In 2023, Clop and LockBit affiliates abused CVE-2023-27350 and CVE-2023-27351 in the same software.

Help Net Security · 15d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078CVE-2023-27350+1 CVEs1

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

PaperCut Zero-Day Under Active Attack: Emergency Patch Released

PaperCut warns that a zero-day in NG and MF print management products is being actively exploited, shipping emergency patches with no CVE assigned yet.

PaperCut Software confirmed active exploitation of a zero-day affecting PaperCut NG and MF, with confirmed customer incidents, and released emergency patches on Friday ahead of technical details or a CVE assignment. The company urges customers to restrict web access to trusted IP addresses, disconnect application servers from the internet, and watch for indicators including tampered or truncated server.log files, database error strings, and suspicious activity involving pc-app.exe. The article recalls the May 2023 exploitation of CVE-2023-27350 and CVE-2023-27351 by the financially motivated Lace Tempest group, a Clop ransomware RaaS affiliate, though no attacker attribution has been given for the current campaign.

Security Affairs · 17d agoExploit / PoC in the wildCVE-2023-27350CVE-2023-273511

Hackers Are Probing PaperCut Servers, and 47% Still Have No Patch

PaperCut pre-auth RCE CVE-2026-81578 actively exploited; 47% of tracked installs unpatched and exposed to remote code execution.

Huntress confirmed active exploitation of a pre-authentication RCE flaw in PaperCut (CVE-2026-81578), chainable with CVE-2026-82078 to achieve SYSTEM-level code execution via PaperCut's Application Server. Observed attacks focused on short reconnaissance (whoami, ver, tasklist) with no persistence, but a malicious Java class dropping into the installation directory leaves the jdbc:derby:memory:pwn breadcrumb. Roughly 47% of ~2,500 tracked installations run version 23 or earlier with no patch yet available.

Security Affairs · 10d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078

U.S. CISA adds PaperCut NG/MF flaws to its Known Exploited Vulnerabilities catalog

CISA added two actively exploited PaperCut NG/MF pre-auth flaws to the KEV catalog; federal agencies must patch by September 14.

CISA added CVE-2026-81578 (CVSS 8.8, missing authentication for critical function) and CVE-2026-82078 (CVSS 9.4, unsafe reflection) in PaperCut NG/MF to its Known Exploited Vulnerabilities catalog. Huntress confirmed active pre-authentication RCE exploitation in two customer environments and reproduced the full chain against a clean PaperCut NG 25.0.11 server, chaining the auth bypass into unsafe Java class loading for SYSTEM-level execution. About 47% of roughly 2,500 tracked PaperCut installs still run version 23 or earlier with no patch available, and observed attacker activity was limited to system discovery commands.

Security Affairs · 15d agoVulnerability in the wildCVE-2026-81578CVE-2026-82078

PaperCut warns of hackers using printer management software flaw in attacks

PaperCut warns of active exploitation of CVE-2026-82078 and CVE-2026-81578 in NG/MF print management software used by universities, corporations, and governments.

PaperCut issued an emergency advisory saying vulnerabilities in PaperCut NG and MF, tracked as CVE-2026-82078 and CVE-2026-81578 with severity scores above 8.8, are under active exploitation with confirmed customer incidents. Huntress reported at least two customers impacted, and an initial patch was revised with input from Huntress and watchTowr researchers. PaperCut software is widely deployed at universities, corporations, and governments managing printers from Canon, Epson, Xerox, and Brother, and the vendor urged removing server web interfaces from the public internet. Previous PaperCut flaws were used by ransomware gangs like Bl00dy and Clop, and CISA has warned the education sector is particularly exposed.

The Record · 18d agoExploit / PoC in the wildCVE-2026-82078CVE-2026-81578

Agents Gone Wild: An AI-Orchestrated Global Campaign Against PaperCut NG/MF

AI-orchestrated campaign exploited PaperCut NG/MF RCE (CVE-2026-81578/82078), compromising 440+ instances at 395 organizations in 48 countries.

GreyNoise tracked a likely Russian-speaking actor using AI (OpenAI Codex harness plus a DeepSeek model) to develop, test, and deploy exploits for PaperCut NG/MF (CVE-2026-81578, CVE-2026-82078) starting 31 August 2026. The actor compromised at least 440 PaperCut instances across 395 organizations in 48 countries, achieving domain admin at 12 victims — fastest time to domain admin was five minutes and a US high school was fully compromised in seven minutes. Attack paths involved LSASS memory and registry secret harvesting, pass-the-hash to domain controllers, noPac attacks, account additions to Domain Admins, and DCSync to exfiltrate full NTDS.DIT credential dumps. Impact scope suggests access development potentially for handoff, with prior PaperCut intrusions historically leading to extortion.

GreyNoise · 7d agoThreat actor in the wildCVE-2026-81578CVE-2026-82078CVE-2021-42278+1 CVEs1

PaperCut Zero-Day Exploited in Attacks, Affecting All NG and MF Versions

PaperCut warns of actively exploited zero-day RCE chain CVE-2026-81578 and CVE-2026-82078 affecting all PaperCut NG and MF versions.

PaperCut alerted customers that attackers are actively exploiting a zero-day affecting all versions of PaperCut NG and MF print management software, with confirmed customer incidents and an ongoing investigation. Emergency patches were released for v25 and v26, and the flaw was later identified as an exploitation chain of CVE-2026-81578 and CVE-2026-82078 enabling remote code execution. Shared IoCs include suspicious post-exploitation activity from pc-app.exe and missing, truncated or deleted server.log files with specific database errors. Users with internet-exposed PaperCut Application Servers are urged to immediately restrict access to trusted IPs; in 2023, CVE-2023-27350 (CVSS 9.8) in the same products was exploited by Lace Tempest to deliver Cl0p and LockBit ransomware.

PaperCut Flaws Exploited in Attacks on U.S. and European Schools

Attackers are chaining recently disclosed PaperCut flaws CVE-2026-81578 and CVE-2026-82078 to steal credentials and create privileged accounts at US and European schools.

Arctic Wolf researchers observed threat actors exploiting PaperCut servers via CVE-2026-81578 and CVE-2026-82078, chaining an authentication bypass with remote code execution. Post-exploitation included creating a privileged account named Administrator17, downloading credential-harvesting tools with certutil, Meterpreter Java payloads, and registry hive collection to recover the Windows BootKey and reach the SAM database. PaperCut disclosed active exploitation on August 27, 2026, and CISA added both flaws to its Known Exploited Vulnerabilities catalog on August 31. PaperCut has a history of exploitation, including attacks that delivered LockBit ransomware.

Security Affairs · 10d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078

AI-powered attack exploited PaperCut flaws to hack 395 organizations

AI-driven campaign exploited PaperCut flaws CVE-2026-81578 and CVE-2026-82078, compromising 440 servers at 395 organizations in 48 countries.

GreyNoise reports a likely Russian-speaking threat actor used hundreds of AI agents combining OpenAI Codex and DeepSeek models to build, test, and refine exploits for CVE-2026-81578 and CVE-2026-82078 in PaperCut NG/MF, launching the campaign on August 31. At least 440 PaperCut instances at 395 organizations across 48 countries were compromised, with the education sector accounting for roughly half of victims and the US most targeted. Attackers harvested credentials from 280 victims, obtained OS or domain secrets from 147, and gained admin privileges at 12 organizations, using LSASS dumping, pass-the-hash, noPac, and DCSync to dump NTDS.DIT. The adversary went from empty workspace to first RCE in under four hours, and compromised at least 11 organizations within 26 seconds once the campaign launched.

BleepingComputerupdated · 5d agofirst · 5d agoExploit / PoC in the wild 8 sourcesCVE-2026-81578CVE-2026-82078CVE-2021-42278+1 CVEs1· 1 read

PaperCut security advisory (AV26-858) – Update 2

CISA added actively exploited PaperCut MF/NG flaws CVE-2026-81578 and CVE-2026-82078 to KEV; Canada's Cyber Centre urges Emergency Patch Release 2 for v24-v26.

Canada's Cyber Centre updated security advisory AV26-858, noting PaperCut MF and PaperCut NG versions prior to the v24, v25, and v26 Emergency Patch Release 2 are affected by CVE-2026-81578 and CVE-2026-82078. Open-source reporting indicates both vulnerabilities are being exploited in the wild. In Update 2 (August 31, 2026), CISA added both CVEs to its Known Exploited Vulnerabilities catalog, and the Cyber Centre urges administrators to apply the emergency patches immediately.

Attackers Exploit PaperCut Flaws to Steal Credentials From Schools and Universities

Attackers exploit newly disclosed PaperCut auth bypass CVE-2026-81578 and RCE CVE-2026-82078 to steal credentials from schools and universities in the US and Europe.

Arctic Wolf observed threat actors chaining CVE-2026-81578 (authentication bypass) and CVE-2026-82078 (remote code execution) in PaperCut to execute commands, perform reconnaissance, and create privileged accounts on servers at K-12 schools and universities in the US and Europe. Post-exploitation includes registry hive collection with lsa_collect.exe delivered via certutil, Meterpreter Java payloads from 194.180.48.134, and searches of PaperCut config files for passwords, LDAP bindings, and tokens. Stolen logins could provide a pathway into other critical systems across compromised environments.

The Hacker News · 11d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-820781

Print management outfit PaperCut is under 0-day attack, and it’s drawing customers’ blood

PaperCut print management software is under active zero-day attack, with only an unofficial emergency patch or server shutdown available as mitigation.

Attackers are actively exploiting an unpatched zero-day vulnerability in PaperCut print management software. The only available fix is an unvalidated, unofficial emergency patch, or taking affected servers offline. PaperCut is widely deployed in enterprise environments, giving exposed instances a broad and consequential attack surface.

The Register · Security · 19d agoExploit / PoC in the wild

August 2026 CVE Landscape

Insikt Group catalogs 73 high-impact August 2026 CVEs (43 Very Critical), including PaperCut, Zimbra, and Metabase flaws actively exploited or weaponized.

Recorded Future's Insikt Group identified 73 high-impact vulnerabilities in August 2026, 43 rated Very Critical, spanning 45 vendors with Microsoft accounting for roughly 11%. 31 vulnerabilities surfaced via CISA's KEV catalog, with others validated via open sources, vendor telemetry, and honeypot data. New Nuclei detection templates were released for CVE-2025-62593 (Ray), CVE-2026-72898 (Metabase), and CVE-2026-9198 (IBM Langflow). The report also highlights two AI-assisted operations: UAT-10147 exploited Zimbra, AjaxPro, Nacos, and Telerik servers before using DeepAudit and PentestGPT post-compromise, while a separate Chinese-speaking actor weaponized Hermes Agent and DeepSeek in a failed attempt.

Recorded Future · 8d agoVulnerability in the wildCVE-2025-62593CVE-2026-72898CVE-2026-9198+4 CVEs

CISA Adds Two Known Exploited Vulnerabilities to Catalog

CISA added actively exploited PaperCut NG/MF flaws CVE-2026-81578 and CVE-2026-82078 to the KEV catalog, mandating federal patching.

CISA added two vulnerabilities to its Known Exploited Vulnerabilities catalog based on evidence of active exploitation: CVE-2026-81578 (PaperCut NG/MF missing authentication for critical function) and CVE-2026-82078 (PaperCut NG/MF unsafe reflection). Under Binding Operational Directive 26-04, Federal Civilian Executive Branch agencies are required to prioritize and apply these updates. The KEV listing signals observed exploitation of the PaperCut print management platform.

CISA Advisories · 15d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078

Thai Broadband Provider Hacked via Fortinet Vulnerability

Hackers exploited Fortinet CVE-2024-21762 RCE to breach Thai broadband provider 3BB, deploying MeshCentral backdoors and credential-harvesting tools across its network.

Hunt.io uncovered an intrusion staging directory in Thailand containing 298 files of custom tooling built for Triple T Broadband (3BB) and its former owner Jasmine. Initial access came via fingerprinting a FortiGate SSL-VPN appliance and exploiting CVE-2024-21762 for remote code execution, after probing CVE-2018-13379, CVE-2022-42475, and CVE-2023-27997. The actor also probed F5 BIG-IP for CVE-2021-22986, CVE-2022-1388, and CVE-2023-46747, escalated privileges with PwnKit and Dirty COW, used MeshCentral as a C2 backdoor, harvested SSH/database/SNMP/Radius credentials, deployed PHP web shells, and ran cleanup scripts to hide the intrusion.

SecurityWeek · 21h agoThreat actor in the wildCVE-2018-13379CVE-2022-42475CVE-2023-27997+4 CVEs

Three JFrog Artifactory Flaws Exploited for Backdoor Deployment

Wiz reports multiple actors chaining three JFrog Artifactory auth flaws to gain admin and deploy backdoors; CISA added all three CVEs to KEV.

Wz reports threat actors exploiting CVE-2026-42018, CVE-2026-42016, and CVE-2026-82329 in self-hosted JFrog Artifactory instances to bypass authentication and gain administrative privileges. Between August 15 and September 8, 2026, multiple actors chained CVE-2026-42018 and CVE-2026-42016 to mint anonymous-user tokens, escalate privileges, create persistent admin accounts, install malicious plugins for code execution, and drop second-stage payloads. From early September, CVE-2026-82329 was exploited for configuration exfiltration, cluster key theft, token minting, and SSH key attachment to attacker-created accounts. CISA added all three CVEs to its KEV catalog, giving federal agencies two weeks under BOD 26-04 to patch to versions 7.161.20, 7.146.38, 7.133.29, 7.125.20, 7.117.28, or 7.111.21.

Check Point Patches Critical VPN Vulnerabilities

Check Point patches two critical unauthenticated RCE flaws (CVE-2026-85102, CVE-2026-85103) in VPN gateways and firewalls; no exploitation observed.

Check Point released patches for CVE-2026-85102 and CVE-2026-85103, two critical vulnerabilities (CVSS 9.8) enabling unauthenticated remote code execution in products using VPN functionality. CVE-2026-85102 involves improper validation of certificate data during VPN negotiation, while CVE-2026-85103 is a heap overflow in the VPN certificate ASN.1 decoding flow. Updates cover versions R82.10, R82, and R81.20; manually defining VPN rules is offered as a mitigation, though it does not apply to locally managed Spark Firewall instances. Check Point discovered both flaws internally and reports no evidence of exploitation in the wild.

SecurityWeekupdated · 2d agofirst · 4d agoVulnerability 9 sourcesCVE-2026-85102CVE-2026-85103CVE-2026-16232+1 CVEs1

Risky Bulletin: Two TeamPCP members arrested in Australia

Australian Federal Police arrested two alleged TeamPCP members behind supply-chain worm attacks that stole over 500,000 credentials from compromised open-source libraries.

The AFP arrested alleged TeamPCP leader Ruben Thomson, 21, and Louis Gaebler, 23, near Perth; both were charged and remain in custody. The group inserted a self-spreading credential-stealing worm into open-source projects including Trivy, KICS, LiteLLM, and Telnyx, harvesting more than 500,000 credentials used for network access, ransomware, extortion, and sales. About 78,000 tokens and secrets from nearly 2,200 organizations leaked online last month, and the FBI supported the investigation that began in April.

Risky Business News · 19d agoPolicy & legal in the wild1