OS Command Injection Vulnerability in E-Series Linksys Routers
CVE-2025-34037

10CRITICAL

Key Information:

Vendor

Linksys
Status
E4200
E3200
E3000
E2500 V1/v2
Vendor
CVE Published:
24 June 2025

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2025-34037?

An OS command injection vulnerability is present in various E-Series Linksys routers, specifically through the /tmUnblock.cgi and /hndUnblock.cgi endpoints accessed over HTTP on port 8080. This security flaw arises from the failure to properly sanitize user-supplied input sent to the ttcp_ip parameter, allowing unauthorized attackers to inject shell commands. The vulnerability has been actively exploited in the wild by the malicious 'TheMoon' worm, which deploys a MIPS ELF payload for arbitrary code execution on the compromised router. Additional Linksys products, such as WAG, WAP, WES, WET, WRT models, and Wireless-N access points, may also be affected by this security issue.

Affected Version(s)

E1000 v1 0 < 2.1.03

E1200 v1 0 <= 1.0.04

E1500 v1 0 < 1.0.06

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-2025-34037 - Proof of Concept

References

https://isc.sans.edu/diary/17633
technical-description
https://www.exploit-db.com/exploits/31683
third-party-advisoryexploit
https://vulncheck.com/advisories/linksys-routers-command-...
third-party-advisory

CVSS V4

Score:
10
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

Johannes Ullrich of SANS Internet Storm Center
.
CVE-2025-34037 : OS Command Injection Vulnerability in E-Series Linksys Routers