CVE-2021-21805 (GCVE-0-2021-21805)

Vulnerability from cvelistv5 – Published: 2021-08-05 20:03 – Updated: 2024-08-03 18:23
VLAI Previdian
Summary
An OS Command Injection vulnerability exists in the ping.php script functionality of Advantech R-SeeNet v 2.4.12 (20.10.2020). A specially crafted HTTP request can lead to arbitrary OS command execution. An attacker can send a crafted HTTP request to trigger this vulnerability.
Severity
9.8 (Critical)
CVSS:3.0/AV:N/AC:L/PR:N/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
n/a Advantech Affected: Advantech R-SeeNet 2.4.12 (20.10.2020)
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 086b923e-d811-4103-9086-f80559427cdc

Vulnerability ID: CVE-2021-21805

Status: Confirmed

Status Updated: 2026-06-06 02:00 CEST

Exploited: Yes

Timestamps
First Seen: 2026-06-06
Asserted: 2026-06-06
Scope
Notes: An OS Command Injection vulnerability exists in the ping.php script functionality of Advantech R-SeeNet v 2.4.12 (20.10.2020). A specially crafted... | Affected: Advantech / R-SeeNet | CVSS: 9.8 (CRITICAL) | EPSS: 0.69842 | Used in malware: unknown | Not yet in CISA KEV: True
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: previdian

Details
Feed Previdian (previdian.com)
Title An OS Command Injection vulnerability exists in the ping.php script functionality of Advantech R-SeeNet v 2.4.12 (20.10.2020). A specially crafted...
Cve Id CVE-2021-21805
Vendor Advantech
Ghsa Id None
Product R-SeeNet
Added Date 2026-06-06T00:00:00.000Z
Cvss Score 9.8
Epss Score 0.69842
Previous Ids
Cvss Severity CRITICAL
Virtual Patch False
Cvss Estimated False
Epss Percentile 0.99355
Used In Malware unknown
Vulnerability Id CVE-2021-21805
Ahead Of Cisa Kev None
Not Yet In Cisa Kev True
References
Created: 2026-10-02 09:09 CEST | Updated: 2026-10-02 09:09 CEST
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.

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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.
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  • 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.



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