ZeroHour
DashboardNewsCVEsExploitsIncidentsAIBriefAnalyticsEntitiesWatchlistIOCsAsk the feedSourcesFeeds & APIKiosk mode

Search: “PaperCut”

35 stories

Searchkeywordsmart Sortlatesthotimportancerelevance
DomainAllCyberAIWindow24h3d7d30dAllIn the wildImportant onlyShow duplicates
CategoryAllExploit / PoC 40Ransomware 38Vulnerability 18Threat actor 7Malware 5Industry 3AI safety & security 2Policy & legal 2Tools 1Research 1Data breach 1
SeverityAllcritical 58high 48medium 5low 0info 7

CVE-2026-81578 + CVE-2026-82078 | PaperCut NG/MF Authentication Bypass and Unsafe Dynamic Class Loading Vulnerabilities

Two chained PaperCut NG/MF flaws, CVE-2026-81578 and CVE-2026-82078, enable pre-auth RCE, with active exploitation confirmed in customer environments.

PaperCut NG/MF is affected by CVE-2026-81578, an improper access control flaw (CVSS 4.0 8.8) allowing unauthenticated configuration changes, and CVE-2026-82078, an unsafe dynamic class loading flaw (CVSS 4.0 9.4) enabling arbitrary Java bytecode execution. Chained, they yield pre-authentication remote code execution on the PaperCut Application Server. PaperCut confirmed active exploitation and customer incidents, and Huntress observed exploitation starting August 26, 2026. Emergency Patch Release 2 is available for NG/MF v24-v26, with IOCs including suspicious pc-app.exe child processes, truncated server.log files, and AnyDesk installs.

Horizon3.ai · 14d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-820781

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

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

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.

The Hacker News · 16d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078CVE-2023-273501

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 NG/MF Critical Zero-Day Exploited in the Wild

PaperCut confirms active exploitation of critical zero-days CVE-2026-81578 and CVE-2026-82078 in PaperCut NG/MF print management software, with confirmed customer incidents.

PaperCut Software issued an urgent advisory on August 27, 2026, confirming it is investigating active exploitation of flaws in PaperCut NG and PaperCut MF and treating the issue as a security emergency. On August 28 the vendor assigned CVE-2026-81578 and CVE-2026-82078 to the two vulnerabilities forming the exploit chain. At initial disclosure, no CVSS score, vulnerability class, authentication requirements, or exploit path details were public. Rapid7 is tracking the issue as an emerging threat.

Rapid7 Blog · 19d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078

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.

Canadian Centre for Cyber Security · 15d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078

PaperCut NG/MF Zero-day Vulnerability Exploited in the Attacks (CVE-2026-82078 & CVE-2026-81578)

PaperCut NG/MF zero-days CVE-2026-82078 and CVE-2026-81578 are actively exploited, chaining to pre-auth RCE on the Application Server.

PaperCut issued an urgent security advisory for two actively exploited vulnerabilities, CVE-2026-82078 and CVE-2026-81578, affecting all versions of PaperCut NG and PaperCut MF. When chained, the flaws enable pre-authentication remote code execution on the PaperCut Application Server, originating from a request-confusion and authorization gap. PaperCut is widely deployed for print management in enterprises and education, making unpatched instances a high-value target.

Qualys ThreatPROTECT · 16d agoExploit / PoC in the wildCVE-2026-82078CVE-2026-81578

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

PaperCut Zero-Day: Active Exploitation and Pre-Auth RCE

PaperCut NG/MF hit by a pre-auth RCE zero-day under active exploitation; Huntress reproduced the chain and urged immediate patching.

Huntress reports active exploitation of a zero-day in PaperCut NG and PaperCut MF, and says it reproduced a pre-authentication remote code execution chain. The flaw allows unauthenticated attackers to execute code on exposed PaperCut servers. Huntress published urgent patching, exposure-reduction, and detection guidance. No CVE identifier was provided in the announcement.

Huntress · 19d agoExploit / PoC in the wild

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

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 · 16d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078

Week in review: Linux rootkit deployed on F5 BIG-IP APM devices, Cisco FMC bugs exploited

Weekly roundup: Cisco FMC and N-able N-central zero-days exploited in the wild, MikroTik RouterOS hijacks, Microsoft Patch Tuesday ships two exploited zero-days.

State-sponsored and financially-motivated attackers are actively exploiting CVE-2026-20079, a critical authentication bypass in Cisco Secure Firewall Management Center (FMC), alongside CVE-2026-20316. N-able issued an emergency hotfix for CVE-2026-86218, a critical pre-auth RCE in the N-central RMM platform exploited in the wild. CERT Polska disclosed six RouterOS vulnerabilities being chained to hijack internet-exposed MikroTik devices. Microsoft's September 2026 Patch Tuesday shipped a record patch count including two zero-days, while roughly 67,000 Trezor customers faced phishing after a shipping-partner breach and researchers privately disclosed a zero-click WeChat worm to Tencent.

Help Net Security · 3d agoExploit / PoC in the wildCVE-2026-20079CVE-2026-20316CVE-2026-862182· 1 read

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.

SecurityWeek · 2d agoExploit / PoC in the wild 7 sourcesCVE-2026-42016CVE-2026-42018CVE-2026-82329

ConnectWise Patches ScreenConnect Vulnerability Exploited in Worm-Like Attacks

ConnectWise patched critical ScreenConnect flaw CVE-2026-84869 (CVSS 9.9) exploited since August 20 in worm-like attacks; CISA added it to KEV.

ConnectWise released urgent patches for CVE-2026-84869 (CVSS 9.9), a missing authorization and improper privilege management flaw in ScreenConnect allowing file transfer and execution through active remote sessions without host confirmation. Huntress reported in-the-wild exploitation since August 20, with attackers using rogue ScreenConnect clients to push four VBScript files for persistence and worm-like propagation to other ScreenConnect clients. The flaw is fixed in ScreenConnect 26.6.5, with disabling the TransferFiles permission as a temporary mitigation. CISA added the CVE to its KEV catalog, requiring federal agencies to patch within three days under BOD 26-04.

SecurityWeekupdated · 1h agofirst · 2d agoExploit / PoC in the wild 4 sourcesCVE-2026-848691

GitLab Vulnerability Exploited One Day After Disclosure

WatchTowr observed in-the-wild exploitation of critical GitLab path traversal CVE-2026-85706 one day after disclosure, letting unauthenticated attackers read arbitrary files.

WatchTowr detected the first in-the-wild probes for CVE-2026-85706 (CVSS 10.0), an unauthenticated path traversal in GitLab CE/EE that allows arbitrary file reads via a single HTTP request, and warns mass exploitation is likely. Affected versions include 18.7 before 19.1.8, 19.2 before 19.2.6, and 19.3 before 19.3.2. The fresh patches also fix 17 other vulnerabilities, including CVE-2026-87719 (CVSS 9.9), an insecure deserialization flaw in the GraphQL subscription serializer exposing Advanced Search credentials, plus six high-severity bugs enabling RCE, CI/CD variable access, XSS, and denial of service.

SecurityWeekupdated · 1d agofirst · 4d agoExploit / PoC in the wild 17 sourcesCVE-2026-85706CVE-2026-877192· 1 read