CVE-2021-21799
published 2021-07-16CVE-2021-21799: Cross-site scripting vulnerabilities exist in the telnet_form.php script functionality of Advantech R-SeeNet v 2.4.12 (20.10.2020). If a user visits a…
PriorityP344medium6.1CVSS 3.1
AVNACLPRNUIRSCCLILAN
EXPLOIT
EPSS
12.29%
95.7th percentile
Cross-site scripting vulnerabilities exist in the telnet_form.php script functionality of Advantech R-SeeNet v 2.4.12 (20.10.2020). If a user visits a specially crafted URL, it can lead to arbitrary JavaScript code execution in the context of the targeted user’s browser. An attacker can provide a crafted URL to trigger this vulnerability.
Affected
1 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| advantech | r-seenet | — | — |
Detection & IOCsextracted from sources · hover to see the quote
url/php/telnet_form.php?hostname=%3C%2Ftitle%3E%3Cscript%3Ealert%28document.domain%29%3C%2Fscript%3E%3Ctitle%3E
- →HTTP GET request to /php/telnet_form.php with a crafted `hostname` parameter containing URL-encoded XSS payload; look for reflected script content in the response body.
- →Response body contains the string 'Telnet alert(document.domain)' indicating successful XSS reflection in the telnet_form.php page.
- →Shodan query 'http.html:"R-SeeNet"' or 'http.html:"r-seenet"' can be used to identify exposed Advantech R-SeeNet instances.
- →FOFA query 'body="r-seenet"' can be used to identify exposed Advantech R-SeeNet instances.
- ·The XSS is reflected (not stored); exploitation requires the victim to visit a specially crafted URL, meaning detection should focus on inbound GET requests with encoded script tags in the `hostname` parameter rather than persistent payload storage. ↗
CVSS provenance
nvdv3.16.1MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
nvdv3.09.6CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:N/I:P/A:N
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Nuclei
Advantech R-SeeNet 2.4.12 - Cross-Site Scripting
nuclei·CVSS 6.1
CVE-2021-21799 [MEDIUM] Advantech R-SeeNet 2.4.12 - Cross-Site Scripting
Advantech R-SeeNet 2.4.12 - Cross-Site Scripting
Advantech R-SeeNet 2.4.12 contains a reflected cross-site scripting vulnerability in the telnet_form.php script functionality.
Template:
id: CVE-2021-21799
info:
name: Advantech R-SeeNet 2.4.12 - Cross-Site Scripting
author: arafatansari
severity: medium
description: |
Advantech R-SeeNet 2.4.12 contains a reflected cross-site scripting vulnerability in the telnet_form.php script functionality.
impact: |
Successful exploitation of this vulnerability could allow an attacker to execute arbitrary script code in the context of the victim's browser, potentially leading to session hijacking, defacement, or theft of sensitive information.
remediation: |
Apply the latest security patches or updates provided by Advantech to mitigate the XSS vulner
Talos
Vulnerability Spotlight: Multiple vulnerabilities in Advantech R-SeeNet
blogs_talos·2021-07-15·CVSS 6.1
[MEDIUM] Vulnerability Spotlight: Multiple vulnerabilities in Advantech R-SeeNet
The Talos vulnerability research team discovered these vulnerabilities. Blog by Jon Munshaw.
Cisco Talos recently discovered multiple vulnerabilities in the Advantech R-SeeNet monitoring software.
R-SeeNet is the software system used for monitoring Advantech routers. It continuously collects information from individual routers in the network and records the data into a SQL database. The vulnerabilities Talos discovered exist in various scripts inside of R-SeeNet's web applications.
TALOS-2021-1270 (CVE-2021-21799), TALOS-2021-1271 (CVE-2021-21800) and TALOS-2021-1272 (CVE-2021-21801 - CVE-2021-21803) are all vulnerabilities that could allow an attacker to execute arbitrary JavaScript code in the context of the targeted user's browser. An adversary could exploit any of these vulnerabilit
Talos
Vulnerability Spotlight: Multiple vulnerabilities in Advantech R-SeeNet
blogs_talos·2021-07-15·CVSS 6.1
[MEDIUM] Vulnerability Spotlight: Multiple vulnerabilities in Advantech R-SeeNet
## Vulnerability Spotlight: Multiple vulnerabilities in Advantech R-SeeNet
The Talos vulnerability research team discovered these vulnerabilities. Blog by Jon Munshaw.
Cisco Talos recently discovered multiple vulnerabilities in the Advantech R-SeeNet monitoring software.
R-SeeNet is the software system used for monitoring Advantech routers. It continuously collects information from individual routers in the network and records the data into a SQL database. The vulnerabilities Talos discovered exist in various scripts inside of R-SeeNet's web applications.
TALOS-2021-1270 (CVE-2021-21799), TALOS-2021-1271 (CVE-2021-21800) and TALOS-2021-1272 (CVE-2021-21801 - CVE-2021-21803) are all vulnerabilities that could allow an attacker to execute arbitrary JavaScript code in the context of the t
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2021-07-16
Published