CVE entry · CVE-2026-81578
CVE-2026-81578: PaperCut NG/MF Missing Authentication for Critical Function Vulnerability
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.
- Actively exploited: added to CISA’s KEV catalog on August 31, 2026.
- Use by ransomware: not established so far.
- Remediation deadline for US federal agencies: September 14, 2026.
Description from CISA’s KEV catalog.
What to do
- Check whether your estate includes PaperCut NG/MF, including internet-facing devices.
- Apply the vendor’s patch or mitigations (references below). Failing that, isolate the product or stop using it, as CISA requires of US federal agencies.
- An exploited vulnerability has often been used before it was fixed: look for signs of compromise, especially on internet-facing devices.
References
- Vendor advisory or reference cited by CISA (www.papercut.com)
- NVD entry (NIST)
- CISA KEV catalog