6.9
MEDIUM CVSS 4.0
CVE-2026-77218
PLANET GS-4210-16P2S Stack Buffer Overflow via dispatcher.cgi Credential Handlers
Description

PLANET GS-4210-16P2S firmware before 3.441b260626 contains authenticated stack buffer overflow vulnerabilities in /cgi-bin/dispatcher.cgi. The web_login_first_post handler copies the usrPass POST parameter into a fixed-size stack buffer without length validation, the web_sys_enablePasswd_post handler copies the enbPass POST parameter into a fixed-size stack buffer without length validation, and the web_sys_localUser_post handler copies the usrName and usrPass POST parameters into fixed-size stack buffers without length validation. A remote authenticated attacker can send a crafted request to crash the CGI process or web management service, resulting in denial of service.

INFO

Published Date :

Aug. 28, 2026, 8:19 p.m.

Last Modified :

Aug. 28, 2026, 8:19 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-77218 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Apply firmware update to fix authenticated stack buffer overflow vulnerabilities.
  • Update PLANET GS-4210-16P2S firmware to 3.441b260626 or later.
  • Restrict access to the web management interface.
  • Monitor network traffic for suspicious activity.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-77218.

URL Resource
https://www.planet.com.tw/en/support/security-advisory/10
https://www.vulncheck.com/advisories/planet-gs-4210-16p2s-stack-buffer-overflow-via-dispatcher-cgi-credential-handlers
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-77218 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-77218 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-77218 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-77218 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Aug. 28, 2026

    Action Type Old Value New Value
    Added Description PLANET GS-4210-16P2S firmware before 3.441b260626 contains authenticated stack buffer overflow vulnerabilities in /cgi-bin/dispatcher.cgi. The web_login_first_post handler copies the usrPass POST parameter into a fixed-size stack buffer without length validation, the web_sys_enablePasswd_post handler copies the enbPass POST parameter into a fixed-size stack buffer without length validation, and the web_sys_localUser_post handler copies the usrName and usrPass POST parameters into fixed-size stack buffers without length validation. A remote authenticated attacker can send a crafted request to crash the CGI process or web management service, resulting in denial of service.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-121
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/77xxx/CVE-2026-77218.json">CVE-2026-77218</a>
    Added Reference https://www.planet.com.tw/en/support/security-advisory/10
    Added Reference https://www.vulncheck.com/advisories/planet-gs-4210-16p2s-stack-buffer-overflow-via-dispatcher-cgi-credential-handlers
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.