CVE-2026-82078

PaperCut MF/NG: Unsafe Dynamic Class Loading in Database Connector

  • Critical 9.4
  • Exploited: added to CISA KEV 31 Aug 2026

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.

Key facts

Published
28 Aug 2026
Last changed
13 Sep 2026
Assigned by
PaperCut
KEV added
31 Aug 2026
KEV fix due
14 Sep 2026
EPSS
63.047% likely to be exploited in the next 30 days, higher than 99.215% of CVEs (scores for 15 Nov 2026)
SSVC (CISA)
Exploitation: active; Automatable: no; Technical impact: total

Severity scores

Each score is shown as its source gave it. They are not averaged or merged.

  • 9.4CVSS 4.0, Criticalfrom the CNA (PaperCut)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

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.CISA KEV required action

Historical context and remediation

This reference retains the original CVE publication date. A recent record update does not mean a new attack occurred.

No separately sourced impact summary is available on this page yet. Consult the description, version data and dated exploitation evidence.

Version statuses below come from the CNA. An “unaffected” version is not necessarily a currently supported release or proof of a patch date. EPSS is a dated risk estimate, not a count of historical attacks.

Read the original CVE record.

Affected products

VendorProductVersions
PaperCutPaperCut MF/NG
  • Default status: unaffected
  • 0 up to but excluding 24.1.10 (affected)
  • 25.0.0 up to but excluding 25.0.13 (affected)
  • 26.0.0 up to but excluding 26.0.5 (affected)

Timeline

  1. 28 Aug 2026 CVE-2026-82078 added to CISA KEV
  2. 28 Aug 2026 Published
  3. 31 Aug 2026 Added to the CISA KEV catalogue

Weakness

References