Actively exploited in the wild
PaperCut NG/MF Unsafe Reflection Vulnerability
PaperCut - NG/MF · Listed in the CISA KEV since 2026-08-31. This indicates confirmed attacks in production environments.
Required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CVE-2026-82078
CriticalCVSS 9.1KEVExploitation Probability (EPSS)
High risk76th percentile - higher than 76% of all known CVEs
Summary
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. If an attacker can manipulate system configuration, this enables execution of arbitrary Java bytecode under the security context of the PaperCut server process.
Risk Assessment
An attacker with configuration access can execute arbitrary Java code, leading to full server compromise.
Recommendation
Restrict access to system configuration and update PaperCut to a version with driver validation.
Other vulnerabilities in PaperCut MF/NG
See all- CVE-2026-81578CriticalActively exploited
Improper access control vulnerability in the web management interface of PaperCut MF and PaperCut NG. Under specific conditions, unauthenticated remote requests targeting administrative functions can trigger backend actions before access validation completes, allowing modification of certain system configurations.
- CVE-2026-87739Medium
An improper authentication vulnerability in PaperCut MF/NG allows an unauthenticated remote attacker to trigger report generation. By submitting report generation requests without valid credentials, an attacker can generate reports and gain unauthorized access to sensitive information.
Original NVD description (English source)
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 manipulate system configuration parameters, this enables the execution of arbitrary Java bytecode residing on the application classpath under the security context of the PaperCut server process.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS