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

Overview On August 27, 2026, PaperCut Software published an urgent security advisory stating that it is investigating active exploitation of a vulnerability affecting PaperCut NG and PaperCut MF. PaperCut has confirmed customer incidents and is treating the issue as a security emergency. At the...

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

PaperCut has alerted customers that bad actors are actively exploiting a vulnerability impacting all versions of its PaperCut NG and PaperCut MF print management software in zero-day attacks. The company has released an emergency patch for v25 and v26 to address the issue. It said it's "aware of...

PaperCut NG < 24.1.9.76516 / 25.x < 25.0.12.76510 / 26.x < 26.0.4.76508 Multiple Vulnerabilities

The version of PaperCut NG installed on the remote Windows host is prior to 24.1.9.76516 or 25.x prior to 25.0.12.76510, or 26.x prior to 26.0.4.76508. It is, therefore, affected by the following vulnerabilities: - An authentication bypass vulnerability exists in the web management interface due ...

VulnCheck KEV: CVE-2026-82078

PaperCut NG/MF contains an unsafe reflection vulnerability that allows an attacker to manipulate system configuration parameters and execute arbitrary Java bytecode residing on the application classpath under the security context of the PaperCut server process. This vulnerability can be chained...

VulnCheck KEV: CVE-2026-81578

PaperCut NG/MF contains a missing authentication for critical function vulnerability which allows an unauthenticated remote attacker to modify certain system configurations. This vulnerability can be chained with CVE-2026-82078...

CVE-2026-81578: Authentication Bypass by Primary Weakness

An improper access control vulnerability exists in the web management interface of PaperCut MF and PaperCut NG. Under specific conditions, unauthenticated remote requests targeting administrative functions can trigger backend actions prior to the completion of access validation checks. This allow...

CVE-2026-82078: Use of Externally-Controlled Input to Select Classes or Code

An unsafe dynamic class loading vulnerability exists in the database connection utilities of PaperCut MF and PaperCut NG. The application instantiates database driver classes based on configurable driver names without validating against an allowlist of approved drivers. If an attacker can...

PaperCut MF < 24.1.9.76515 / 25.x < 25.0.12.76509 / 26.x < 26.0.4.76507 Multiple Vulnerabilities

The version of PaperCut MF installed on the remote Windows host is prior to 24.1.9.76515 or 25.x prior to 25.0.12.76509, or 26.x prior to 26.0.4.76507. It is, therefore, affected by the following vulnerabilities: - An authentication bypass vulnerability exists in the web management interface due ...

PT-2026-83118

Name of the Vulnerable Software and Affected Versions PaperCut MF affected versions not specified PaperCut NG affected versions not specified Description An unsafe dynamic class loading issue exists in the database connection utilities. The application instantiates database driver classes based o...

PaperCut NG/MF Unauthenticated RCE (CVE-2026-81578 + CVE-2026-82078)

This module exploits an authentication bypass in PaperCut NG and MF. A crafted Apache Tapestry complex-direct request invokes privileged ConfigEditor components through the public Home page. On version 26, the module reconfigures external user lookup to use an H2 JDBC URL whose initialization SQL...

PT-2026-83117

Name of the Vulnerable Software and Affected Versions PaperCut MF affected versions not specified PaperCut NG affected versions not specified Description An improper access control issue exists in the web management interface. Under specific conditions, unauthenticated remote requests targeting...

PaperCut NG/MF Auth Bypass RCE (CVE-2023-27350)

Exploits CVE-2023-27350 in PaperCut NG/MF before 20.1.7, 21.2.11, and 22.0.9. Unauthenticated access to SetupCompleted grants an admin session, then Rhino print scripting runs self.payload via java.lang.ProcessBuilder. !/usr/bin/env python3 -- coding: utf-8 -- """CVE-2023-27350 — PaperCut NG/MF...

CVE-2026-8793

PaperCut NG/MF does not properly restrict excessive authentication attempts within its login component. An unauthenticated remote attacker can exploit this vulnerability to perform unrestricted brute-force or credential-stuffing attacks without triggering account lockout or rate-limiting mechanis...

CVE-2026-8794

PaperCut NG/MF contains an observable timing discrepancy in its authentication component. An unauthenticated remote attacker can exploit this vulnerability to perform username enumeration by measuring response times during login attempts. The system executes a password hash comparison only when a...

CVE-2026-8794 PaperCut NG/MF: User enumeration via timing attack

PaperCut NG/MF contains an observable timing discrepancy in its authentication component. An unauthenticated remote attacker can exploit this vulnerability to perform username enumeration by measuring response times during login attempts. The system executes a password hash comparison only when a...

CVE-2026-8794

PaperCut NG/MF contains an observable timing discrepancy in its authentication component. An unauthenticated remote attacker can exploit this vulnerability to perform username enumeration by measuring response times during login attempts. The system executes a password hash comparison only when a...

EUVD-2026-52225

PaperCut NG/MF contains an observable timing discrepancy in its authentication component. An unauthenticated remote attacker can exploit this vulnerability to perform username enumeration by measuring response times during login attempts. The system executes a password hash comparison only when a...

CVE-2026-8794 PaperCut NG/MF: User enumeration via timing attack

PaperCut NG/MF contains an observable timing discrepancy in its authentication component. An unauthenticated remote attacker can exploit this vulnerability to perform username enumeration by measuring response times during login attempts. The system executes a password hash comparison only when a...

CVE-2026-8794

PaperCut NG/MF is affected by a timing-based user enumeration vulnerability in its authentication component. An unauthenticated remote attacker can detect whether a login target exists by measuring response times, since the system only performs a password hash comparison after confirming a valid ...

CVE-2026-8793 PaperCut NG/MF: Insufficient brute-force protection

PaperCut NG/MF does not properly restrict excessive authentication attempts within its login component. An unauthenticated remote attacker can exploit this vulnerability to perform unrestricted brute-force or credential-stuffing attacks without triggering account lockout or rate-limiting mechanis...