— Unscored

PaperCut NG/MF Missing Authentication for Critical Function Vulnerability

CVE-2026-81578 Exploited

PaperCut NG/MF contains a missing authentication for critical function vulnerability which allows an unauthenticated remote attacker to modify certain system configurations. This vulnerability can be chained with CVE-2026-82078.

Being exploited in the wild

Catalogued 31 August 2026 · US federal remediation deadline 14 September 2026

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…

Exploit code is also public: Metasploit · Public PoC · Nuclei template

Metasploitexploit/multi/http/papercut_ng_external_user_lookup_rce
NucleiPaperCut NG/MF <=26.0.4 - Unauthenticated ConfigEditor Access via Tapestry Complex-Direct
Public PoCyora1928/PaperCut-CVE-2026-81578-820784 stars
Public PoCvirologi-info/papercut-toolkit2 stars

Assessment

CVSS: Not yet scored
Severity: Unscored
Known exploited: Yes — listed in the CISA KEV catalog
Exploit availability: CISA KEV, Metasploit, Public PoC, Nuclei template
Published: 31 August 2026
Last updated: 31 August 2026
Affected: PaperCut · NG/MF
Weakness: CWE-306

At the source

CISA KEV

References

https://www.cisa.gov/known-exploited-vulnerabilities-catalog

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