CVE-2020-29390 (GCVE-0-2020-29390)

Vulnerability from cvelistv5 – Published: 2020-11-30 17:24 – Updated: 2024-08-04 16:55
VLAI Shadowserver
Summary
Zeroshell 3.9.3 contains a command injection vulnerability in the /cgi-bin/kerbynet StartSessionSubmit parameter that could allow an unauthenticated attacker to execute a system command by using shell metacharacters and the %0a character.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CWE
  • n/a
Assigner
mitre CNA under the mitre root
CNA scorecard E 29/100 over 2315 records in the last 180 days details
References
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 5fddc41b-f2e8-49d0-aa08-e4c8864ce2db

Vulnerability ID: CVE-2020-29390

Status: Confirmed

Status Updated: 2026-10-25 00:00 UTC

Exploited: Yes

Characteristics
Severity: 98.0
Timestamps
First Seen: 2026-09-22
Asserted: 2026-09-22
Last Seen: 2026-10-25
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: Zeroshell / Zeroshell Linux Router | Class: embedded-system | Severity: Critical (CVSS 9.8) | IoT: yes | In CISA KEV: no | Honeypot connections on 2026-10-25: 4
Evidence

Type: Honeypot

Signal: In The Wild Attempts

Confidence: 70%

Source: shadowserver

Details
1D 2
Iot yes
Feed Shadowserver Foundation honeypot/exploited-vulnerabilities
Type http-scan
Class embedded-system
7D Avg 1
Vendor Zeroshell
30D Avg 3
90D Avg 1
Product Zeroshell Linux Router
Cisa Kev no
Connections 4
Observation Date 2026-10-25
Vulnerability Class CVSS
Vulnerability Score 9.8
Vulnerability Severity Critical
References
Created: 2026-10-21 09:13 UTC | Updated: 2026-10-27 01:00 UTC
Show details on NVD website
To clipboard 

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