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CVE-2021-41653 (GCVE-0-2021-41653)

Vulnerability from cvelistv5 – Published: 2021-11-13 14:18 – Updated: 2026-07-09 00:15
VLAI Shadowserver Previdian
Summary
The PING function on the TP-Link TL-WR840N EU v5 router with firmware through TL-WR840N(EU)_V5_171211 is vulnerable to remote code execution via a crafted payload in an IP address input field.
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: d9b7a7b3-9303-4526-8424-ae795fc52c62

Vulnerability ID: CVE-2021-41653

Status: Confirmed

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

Exploited: Yes

Characteristics
Severity: 98.0
Timestamps
First Seen: 2023-10-14
Asserted: 2023-10-14
Last Seen: 2026-07-19
Scope
Asset Exposure: ['internet-facing']
Notes: Affected: TP-Link / TP-Link TL-WR840N EU v5 | Class: router | Severity: Critical (CVSS 9.8) | 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 1
Vendor TP-Link
30D Avg 4
90D Avg 4
Product TP-Link TL-WR840N EU v5
Cisa Kev no
Connections 1
Observation Date 2026-07-19
Vulnerability Class CVSS
Vulnerability Score 9.8
Vulnerability Severity Critical
References
Created: 2026-06-30 09:23 UTC | Updated: 2026-07-21 01:02 UTC
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: ad0eff7d-a5c8-4d63-a0b1-305a688ccc99

Vulnerability ID: CVE-2021-41653

Status: Confirmed

Status Updated: 2025-09-18 00:00 UTC

Exploited: Yes

Timestamps
First Seen: 2025-09-18
Asserted: 2025-09-18
Scope
Notes: KEVIntel entry: The PING function on the TP-Link TL-WR840N EU v5 router with firmware through TL-WR840N(EU)_V5_171211 is vulnerable to remote code execution via a... | Affected: TP-Link / TL-WR840N EU v5 router | CVSS: 9.8 (CRITICAL) | 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 The PING function on the TP-Link TL-WR840N EU v5 router with firmware through TL-WR840N(EU)_V5_171211 is vulnerable to remote code execution via a...
Vendor TP-Link
Product TL-WR840N EU v5 router
Added Date 2025-09-18T00:00:00.000Z
Cvss Score 9.8
Epss Score None
Cvss Severity CRITICAL
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

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.


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