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CVE-2021-3708 (GCVE-0-2021-3708)

Vulnerability from cvelistv5 – Published: 2021-08-16 04:55 – Updated: 2024-08-03 17:01
VLAI Shadowserver Previdian
Summary
D-Link router DSL-2750U with firmware vME1.16 or prior versions is vulnerable to OS command injection. An unauthenticated attacker on the local network may exploit this, with CVE-2021-3707, to execute any OS commands on the vulnerable device.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
References
Impacted products
Vendor Product Version CPE status
D-Link DSL-2750U Affected: firmware vME1.16 or prior versions
guessed Create a notification for this product.
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 4f3b9cfd-a409-4463-b0bd-50297305a42f

Vulnerability ID: CVE-2021-3708

Status: Confirmed

Status Updated: 2026-07-19 00:00 UTC

Exploited: Yes

Characteristics
Severity: 55.0
Timestamps
First Seen: 2023-10-20
Asserted: 2023-10-20
Last Seen: 2026-07-19
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: D-Link / D-Link DSL-2750U | Class: router | Severity: Medium (CVSS 5.5) | IoT: yes | In CISA KEV: no | Honeypot connections on 2026-07-19: 1
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 DSL-2750U
Cisa Kev no
Connections 1
Observation Date 2026-07-19
Vulnerability Class CVSS
Vulnerability Score 5.5
Vulnerability Severity Medium
References
Created: 2026-06-30 09:23 UTC | Updated: 2026-07-21 01:01 UTC
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 543aa262-f9c1-4698-8926-93da21dae943

Vulnerability ID: CVE-2021-3708

Status: Confirmed

Status Updated: 2026-01-16 00:00 UTC

Exploited: Yes

Timestamps
First Seen: 2026-01-16
Asserted: 2026-01-16
Scope
Notes: KEVIntel entry: D-Link router DSL-2750U with firmware vME1.16 or prior versions is vulnerable to OS command injection. An unauthenticated attacker on the local... | Affected: D-Link / DSL-2750U | CVSS: 7.8 (HIGH) | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: kevintel

Details
Feed KEVIntel (kevintel.com)
Title D-Link router DSL-2750U with firmware vME1.16 or prior versions is vulnerable to OS command injection. An unauthenticated attacker on the local...
Vendor D-Link
Product DSL-2750U
Added Date 2026-01-16T00:00:00.000Z
Cvss Score 7.8
Epss Score None
Cvss Severity HIGH
Epss Percentile None
Used In Malware unknown
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-06-23 14:03 UTC | Updated: 2026-07-10 06:14 UTC
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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