CVE-2026-81578 — PaperCut MF/NG: Authentication Bypass

Description (CNA)

An improper access control vulnerability exists in the web management interface of PaperCut MF and PaperCut NG. Under specific conditions, unauthenticated remote requests targeting administrative functions can trigger backend actions prior to the completion of access validation checks. This allows an unauthenticated remote attacker to modify certain system configurations.

Affected (CNA)

Vendor / product	Versions
PaperCut / PaperCut MF/NG	affected 0 before 24.1.10; affected 25.0.0 before 25.0.13; affected 26.0.0 before 26.0.5

CWE

CWE-305

References

https://www.papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-advisory/

ADP enrichment

CISA-ADP

No English description supplied.

https://github.com/rapid7/metasploit-framework/pull/21842
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81578