PaperCut · NG/MF
CVE-2026-82078
PaperCut MF/NG: Unsafe Dynamic Class Loading in Database Connector
What it is
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.
CISA: 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 with CVE-2026-81578.
What to do
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.
Deadline for US federal agencies: September 14, 2026
More exploited flaws from PaperCut
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| Aug 31, 2026 | Missing Authentication for Critical Function | NG/MF | High 8.8 | 84% |
| Apr 20, 2026 | Improper Authentication | NG/MF | High 8.2 | 78% |
| Jul 28, 2025 | Cross-Site Request Forgery (CSRF) | NG/MF | High 8.4 | 29% |
| Apr 21, 2023 | Improper Access Control | MF/NG | Critical 9.8 | >99.9% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.