Actively exploited · Published Aug 28, 2026 · Assigned by PaperCut
CVE-2026-82078PaperCut MF/NG: Unsafe Dynamic Class Loading in Database Connector
Critical 9.4 Exploited
In plain English
A critical-severity security flaw in PaperCut MF/NG from PaperCut. Attackers are actively exploiting it in the wild (listed by CISA on August 31, 2026). The chance it is exploited in the next 30 days is estimated at 63.0% (higher than 99.2% of all known vulnerabilities). Ready-made attack tooling exists: Metasploit. 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.
CISA guidance
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.
Federal agencies must remediate by Sep 14, 2026.
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| PaperCut | PaperCut MF/NG | 0 – before 24.1.1025.0.0 – before 25.0.1326.0.0 – before 26.0.5 |
Weakness: CWE-470 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H