CVE-2025-66620: Columbia Weather Systems MicroServer · Command Shell in Externally Accessible Directory
Affects Columbia Weather Systems MicroServerSource CVE Database V5
Not known to be exploited · CVSS 8.6 High : upgrade to MS_4.1_14142 soon.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 39% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in MS_4.1_14142
CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 7 Jan 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Upgrade Columbia Weather Systems MicroServer to MS_4.1_14142.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Columbia Weather SystemsMicroServer | Affected
| Fixed in
|
AI-suggested
1. Immediately audit all Columbia Weather Systems MicroServer devices to identify the presence of the unused webshell and remove or disable it. 2. Restrict network access to MicroServer devices by implementing strict firewall rules and network segmentation, limiting exposure to trusted management networks only. 3. Enforce strong authentication and authorization controls to prevent unauthorized administrative access to the MicroServer. 4. Monitor logs and network traffic for unusual login attempts or reverse shell activity indicative of exploitation attempts. 5. 6. Implement host-based intrusion detection systems (HIDS) on MicroServer devices to detect unauthorized file modifications or shell access. 7. Conduct regular security assessments and penetration tests focusing on OT and IoT devices like the MicroServer to identify similar vulnerabilities. 8. Develop incident response plans specific to OT environments to quickly contain and remediate any compromise involving these devices.
Description
An unused webshell in MicroServer allows unlimited login attempts, with sudo rights on certain files and directories. An attacker with admin access to MicroServer can gain limited shell access, enabling persistence through reverse shells, and the ability to modify or remove data stored in the file system.