Vulnerability
CVE-2025-52691
SmarterTools Smartermail: unauthenticated arbitrary file upload leading to code execution
Most severe levelDEFCON 4 · Moderate risk
Official data
- CVSS 3.1
- 10.0 · critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-434
- EPSS
- 85.66% probability of exploitation in the next 30 days, higher than 99% of CVEs
- CISA KEV catalogue
- Yes, since 26 January 2026 · used in ransomware campaigns
Sources: NVD (CVSS, weakness, publication), FIRST (EPSS), CISA (KEV catalogue).
Data read on 4 November 2026.
Timeline
- 29 December 2025Published on NVD
- 29 December 2025First in the DefenceLevel briefing
- 26 January 2026Added to the CISA KEV catalogue
In DefenceLevel briefings2 days
- 27 January 2026New in the last 24 hoursDEFCON 4
- 29 December 2025New in the last 24 hoursDEFCON 4
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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