CVE-2021-39509 (GCVE-0-2021-39509)

Vulnerability from cvelistv5 – Published: 2021-08-24 18:52 – Updated: 2024-08-04 02:06
VLAI Shadowserver
Summary
An issue was discovered in D-Link DIR-816 DIR-816A2_FWv1.10CNB05_R1B011D88210 The HTTP request parameter is used in the handler function of /goform/form2userconfig.cgi route, which can construct the user name string to delete the user function. This can lead to command injection through shell metacharacters.
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 28/100 over 2348 records in the last 180 days details
References
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 1f6db9c8-2535-4030-a2a7-b014da1325b8

Vulnerability ID: CVE-2021-39509

Status: Confirmed

Status Updated: 2024-10-09 03:25 UTC

Exploited: Yes

Characteristics
Severity: 98.0
Timestamps
First Seen: 2024-10-09
Asserted: 2024-10-09
Last Seen: 2024-10-09
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: D-Link / D-Link DIR-816/DIR-816A2 | Class: router | Severity: Critical (CVSS 9.8) | IoT: yes | In CISA KEV: no | Honeypot connections on 2024-10-09: 81
Evidence

Type: Honeypot

Signal: In The Wild Attempts

Confidence: 70%

Source: shadowserver

Details
1D 1
Iot yes
Feed Shadowserver Foundation honeypot/exploited-vulnerabilities
Type http-scan
Class router
7D Avg 0
Vendor D-Link
30D Avg 0
90D Avg 0
Product D-Link DIR-816/DIR-816A2
Cisa Kev no
Connections 81
Observation Date 2024-10-09
Vulnerability Class CVSS
Vulnerability Score 9.8
Vulnerability Severity Critical
References
Created: 2026-07-01 09:12 UTC | Updated: 2026-07-01 13:16 UTC
Show details on NVD website
To clipboard 

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