CVE-2021-35327 (GCVE-0-2021-35327)

Vulnerability from cvelistv5 – Published: 2021-08-05 20:39 – Updated: 2024-08-04 00:33
VLAI Shadowserver Previdian
Summary
A vulnerability in TOTOLINK A720R A720R_Firmware v4.1.5cu.470_B20200911 allows attackers to start the Telnet service, then login with the default credentials via a crafted POST request.
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: 2a3f602e-b5c3-44b3-b430-f2a2209cf98f

Vulnerability ID: CVE-2021-35327

Status: Confirmed

Status Updated: 2023-10-13 18:44 UTC

Exploited: Yes

Characteristics
Severity: 98.0
Timestamps
First Seen: 2023-10-13
Asserted: 2023-10-13
Last Seen: 2023-10-13
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: Totolink / A720R | Class: router | IoT: yes | In CISA KEV: no | Honeypot connections on 2022-08-28: 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 1
Vendor Totolink
30D Avg 1
90D Avg 0
Product A720R
Cisa Kev no
Connections 1
Observation Date 2022-08-28
Vulnerability Class None
Vulnerability Score None
Vulnerability Severity None
References
Created: 2026-06-30 12:18 UTC | Updated: 2026-06-30 15:44 UTC
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: aa0203c2-14f0-4d9e-8df1-cc101cebddcf

Vulnerability ID: CVE-2021-35327

Status: Confirmed

Status Updated: 2021-08-05 20:39 UTC

Exploited: Yes

Timestamps
First Seen: 2021-08-05
Asserted: 2021-08-05
Scope
Notes: KEVIntel entry: A vulnerability in TOTOLINK A720R A720R_Firmware v4.1.5cu.470_B20200911 allows attackers to start the Telnet service, then login with the default... | Affected: n/a / n/a | 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 A vulnerability in TOTOLINK A720R A720R_Firmware v4.1.5cu.470_B20200911 allows attackers to start the Telnet service, then login with the default...
Vendor n/a
Product n/a
Added Date 2021-08-05T20:39:17.000Z
Cvss Score None
Epss Score None
Cvss Severity None
Epss Percentile None
Used In Malware unknown
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-06-23 14:06 UTC | Updated: 2026-07-10 06:14 UTC
Show details on NVD website
To clipboard 

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Taxonomy of the tags.





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.



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.