CVE-2026-82078

PaperCut NG/MF Unsafe Reflection Vulnerability

IN CISA KEV

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.

Vendor: PaperCut
Product: NG/MF
CVSS 3.1: 9.1 (critical), scored by NVD (primary)CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
CVSS 4.0: 9.4 (critical), scored by eb41dac7-0af8-4f84-9f6d-0272772514f4CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CWE: CWE-470
Published: 2026-08-28
NVD modified: 2026-09-14
NVD status: Analyzed

CISA KEV

Date added: 2026-08-31
Due date: 2026-09-14
Ransomware use: Unknown
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.

EPSS

63.5% chance of exploitation in the next 30 days (percentile 99th)

FIRST EPSS, updated 17 Oct 2026. About EPSS

CVSS is severity, EPSS is likelihood, KEV means already exploited. EPSS is a statistical probability, not a certainty: a low score does not make a bug safe, and a high one does not prove it is being exploited.

References

www.papercut.com (Patch, Vendor Advisory)
github.com (Issue Tracking, Patch)
www.cisa.gov (Patch, Third Party Advisory, US Government Resource)

Data last updated 18 Oct 2026. Sources: NVD API 2.0, CISA KEV catalog, FIRST EPSS. Links: NVD, CISA KEV. Metadata only. ThreatWire does not host exploit code.