Remote Command Injection in Totolink A7100RU Affected by CGI Handler Flaw
CVE-2026-5853

9.3CRITICAL

Key Information:

Vendor

Totolink
Status
A7100ru
Vendor
CVE Published:
9 April 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-5853?

A security vulnerability has been identified in the Totolink A7100RU firmware version 7.4cu.2313_b20191024, specifically within the CGI Handler component, which allows for remote command injection via the setIpv6LanCfg function in the file /cgi-bin/cstecgi.cgi. An attacker can manipulate the addrPrefixLen parameter leading to execution of arbitrary OS commands. This vulnerability is publicly disclosed and poses a significant security risk.

Affected Version(s)

A7100RU 7.4cu.2313_b20191024

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-5853 - Proof of Concept

References

https://vuldb.com/vuln/356379
vdb-entrytechnical-description
https://vuldb.com/vuln/356379/cti
signaturepermissions-required
https://vuldb.com/submit/791274
third-party-advisory

CVSS V4

Score:
9.3
Severity:
CRITICAL
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

LtzHuster2 (VulDB User)
.