CVE-2026-81578: PaperCut NG/MF · Improper Access Control Vulnerability Exists
Affects PaperCut NG/MFSource GCVE Database
Exploited in the wild · KEV due 14 Sep 2026 · public exploit available (Metasploit) · 83% EPSS · fixed in 26.0.5 : patch PaperCut NG/MF now.
Data as of 26 Oct 2026, 17:16 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else. Other KEV due dates
- EPSS
- 83.7% chance of exploitation in 30 days – higher than 99% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 26.0.5, 25.0.13, 24.1.10
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:NExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 28 Aug 2026
Detectable: evidence found.
Weaponised: evidence found.
Exploited in the wildExploited: evidence found.
Listed in CISA KEV 3 days after disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by PaperCut Software Pty Ltd
, 28 hours before disclosure
CVE published
on cve.org
, t = 0
In Threat Radar
record ingested
, 4 hours after disclosure
Added to CISA KEV (opens in a new tab)
exploitation confirmed
, 3 days after disclosure
KEV remediation due
US federal deadline
, 17 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade PaperCut MF/NG to 26.0.5, 25.0.13 or 24.1.10.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| PaperCutPaperCut MF/NG | Affected
| Fixed in
|
| PaperCutPaperCut MF/NG | Affected
| Fixed in
|
| PaperCutPaperCut MF/NG | Affected
| Fixed in
|
Description
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.
References
- nvd.nist.gov/vuln/detail/CVE-2026-81578 (opens in a new tab)
- github.com/rapid7/metasploit-framework/pull/21842 (opens in a new tab)
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-81578 (opens in a new tab)
- papercut.com/kb/Main/security-bulletin-27-aug-2026-urgent-security-advisory (opens in a new tab)