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CVE-2021-27692 (GCVE-0-2021-27692)

Vulnerability from cvelistv5 – Published: 2021-04-15 23:14 – Updated: 2024-08-03 21:26
VLAI Shadowserver
Summary
Command Injection in Tenda G1 and G3 routers with firmware versions v15.11.0.17(9502)_CN or v15.11.0.16(9024)_CN allows remote attackers to execute arbitrary OS commands via a crafted "action/umountUSBPartition" request. This occurs because the "formSetUSBPartitionUmount" function executes the "doSystemCmd" function with untrusted input.
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
References
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 3396996f-b1d0-484f-9dd4-f1a1aa7b4cd0

Vulnerability ID: CVE-2021-27692

Status: Confirmed

Status Updated: 2025-06-08 17:39 UTC

Exploited: Yes

Characteristics
Severity: 98.0
Timestamps
First Seen: 2025-06-08
Asserted: 2025-06-08
Last Seen: 2025-06-08
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: Tenda / Tenda G1 and G3 | Class: router | Severity: Critical (CVSS 9.8) | IoT: yes | In CISA KEV: no | Honeypot connections on 2025-06-08: 13
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 Tenda
30D Avg 0
90D Avg 0
Product Tenda G1 and G3
Cisa Kev no
Connections 13
Observation Date 2025-06-08
Vulnerability Class CVSS
Vulnerability Score 9.8
Vulnerability Severity Critical
References
Created: 2026-07-01 07:18 UTC | Updated: 2026-07-01 12:45 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

Author Source Type Date Other

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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.