CRITICAL Actively exploited CWE-78
CVE-2020-8515
Multiple DrayTek Vigor Routers Web Management Page Vulnerability
DrayTek·Multiple Vigor Routers
9.8/ 10
CVSS 3.1
Critical severity
>99.9%
EPSS exploit odds
Chance of exploitation in the next 30 days
Among the very highest of all CVEs
Listed
CISA KEV catalog
- Added
- Nov 3, 2021
- Fix due
- May 3, 2022
- Ransomware
- Not known
Timeline
- Published
- Feb 1, 2020
- Updated
- Oct 21, 2025
- First covered
- Jul 27, 2026
- Latest story
- 4 months ago
Summary
DrayTek Vigor2960 1.3.1_Beta, Vigor3900 1.4.4_Beta, and Vigor300B 1.3.3_Beta, 1.4.2.1_Beta, and 1.4.4_Beta devices allow remote code execution as root (without authentication) via shell metacharacters to the cgi-bin/mainfunction.cgi URI. This issue has been fixed in Vigor3900/2960/300B v1.5.1.
CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Attack profile
Attack vectorNetwork
ComplexityLow
PrivilegesNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HCISA required action
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