PaperCut NG/MF vulnerability

PaperCut NG/MF does not properly restrict excessive authentication attempts within its login component. An unauthenticated remote attacker can exploit this vulnerability to perform unrestricted brute-force or credential-stuffing attacks without triggering account lockout or rate-limiting mechanisms in some configurations.

Published 3 Aug 2026Updated 9 Sep 20261 sources
CVSS 6.9

What happened

PaperCut NG/MF does not properly restrict excessive authentication attempts within its login component. An unauthenticated remote attacker can exploit this vulnerability to perform unrestricted brute-force or credential-stuffing attacks without triggering account lockout or rate-limiting mechanisms in some configurations.

Affected versions

PaperCut NG/MF: before 26.0.3 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

No public PoC reference has passed the current publication threshold.