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.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
High
Admin privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 6
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Papercut Papercut_Mf
cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*
|
— |
24.1.9
|
|
Papercut Papercut_Mf
cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*
|
25.0.2
|
25.0.12
|
|
Papercut Papercut_Mf
cpe:2.3:a:papercut:papercut_mf:*:*:*:*:*:*:*:*
|
26.0.2
|
26.0.4
|
|
Papercut Papercut_Ng
cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*
|
— |
24.1.9
|
|
Papercut Papercut_Ng
cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*
|
25.0.2
|
25.0.12
|
|
Papercut Papercut_Ng
cpe:2.3:a:papercut:papercut_ng:*:*:*:*:*:*:*:*
|
26.0.2
|
26.0.4
|
References 3
https://www.papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-…
eb41dac7-0af8-4f84-9f6d-0272772514f4
https://github.com/rapid7/metasploit-framework/pull/21842
134c704f-9b21-4f2e-91b3-4a467353bcc0
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026…
134c704f-9b21-4f2e-91b3-4a467353bcc0