CVE-2026-81578
Critical CVSS 9.8 Known exploitedPublished 2026-08-28 · last changed 2026-09-14 · added to CISA KEV 2026-08-31
The fix
We hold no Microsoft remediation data for CVE-2026-81578, which normally means it is not a Windows CVE. For non-Microsoft software the fix is the vendor's own updated release, and the affected versions are listed below.
What it is
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.
Sources
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H