Vulnerability
CVE-2026-81578
PaperCut NG/MF: missing authentication
Most severe levelDEFCON 3 · Substantial risk
Official data
- CVSS 4.0
- 8.8 · high
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:L/SC:N/SI:N/SA:N - Weakness
- CWE-305
- EPSS
- 85.58% probability of exploitation in the next 30 days, higher than 99% of CVEs
- CISA KEV catalogue
- Yes, since 31 August 2026
Sources: NVD (CVSS, weakness, publication), FIRST (EPSS), CISA (KEV catalogue).
Data read on 4 November 2026.
Timeline
- 28 August 2026Published on NVD
- 31 August 2026Added to the CISA KEV catalogue
- 1 September 2026First in the DefenceLevel briefing
In DefenceLevel briefings5 days
- 13 October 2026New in the last 24 hoursDEFCON 4
- 10 October 2026New in the last 24 hoursDEFCON 4
- 3 September 2026Still ongoingDEFCON 4
- 2 September 2026Still ongoingDEFCON 4
- 1 September 2026New in the last 24 hoursDEFCON 3
Last 12 months.
The full analysis is in the briefingThe full analysis is in your archive
Why it matters now, who is affected and what to do: every day at 05:00 UTC, for subscribers.Why it matters, who is affected and what to do, as in the daily briefing.
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