CVE-2021-21805

9.8

CVSS
Critical

PUBLISHED

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...

Exploited in the wild Remote Low complexity No user interaction

Vendor: Advantech
Product: R-SeeNet
Published: Aug 05, 2021
EPSS: 92.9% · 100% pctl

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Description

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.

php nuclei_scanner

Weaknesses (CWE)

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CVSS scores

CVSS v3.1 9.8 Critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v3.0 9.8 Critical

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2.0 10.0 High

AV:N/AC:L/Au:N/C:C/I:C/A:C

Exploitation status

Exploited in the wild

Recorded 2026-06-06 00:00:00 UTC · The Shadowserver (via CIRCL)

References

https://talosintelligence.com/vulnerability_reports/TALOS-2021-1274

Known exploited vulnerability sources

Catalogues that list this CVE as a known exploited vulnerability.

Source	Added
The Shadowserver (via CIRCL) First	2026-06-06 00:00 UTC

Scanner integrations

Scanner	Reference	Detected
Nuclei	https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-21805.yaml	Apr 25, 2025

Vulnerability detail