Linksys

CVE-2025-34037: Linksys Routers E/WAG/WAP/WES/WET/WRT-Series

Is it exploited?

Reported, not confirmed by CISA. VulnCheck KEV lists it as exploited in the wild. CISA has not added it to its Known Exploited Vulnerabilities catalog as of 29 Oct 2026.

VulnCheck KEV lists it since 23 Jun 2025. It cites 200 public reports, the first from 23 Jun 2025. VulnCheck's own honeypots also recorded exploitation attempts.

How likely is exploitation in the next 30 days?

96.2%

Up from 92.8% on 23 Oct 2026.

EPSS score, percentile 99.9 of all scored records. A probability estimated by FIRST, not a report of exploitation.

CISA's SSVC assessment in the CVE record lists exploitation as poc.

How severe?

10.0 Critical

CVSS v4.0 base score, given by the CNA

What should I do?

CISA has set no required action, because the vulnerability is not in KEV.

The CVE record links no vendor advisory, patch or mitigation.

Which versions are affected?

Affected

before 1.0.06
before 1.0.05
before 1.0.06
before 2.0.00
1.0.05 and earlier
unspecified

and 5 more in the table below

Versions by product

Source: CISA KEV 2026.10.29, as of 29 Oct 2026; VulnCheck KEV, as of 30 Oct 2026; FIRST EPSS, as of 30 Oct 2026; CVE List, as of 30 Oct 2026. About the data.

Description

Linksys Routers E/WAG/WAP/WES/WET/WRT-Series

An OS command injection vulnerability exists in various models of E-Series Linksys routers via the /tmUnblock.cgi and /hndUnblock.cgi endpoints over HTTP on port 8080. The CGI scripts improperly process user-supplied input passed to the ttcp_ip parameter without sanitization, allowing unauthenticated attackers to inject shell commands. This vulnerability was reported to be exploited in the wild by the "TheMoon" worm in 2014 to deploy a MIPS ELF payload, enabling arbitrary code execution on the router. Additionally, this vulnerability may affect other Linksys products to include, but not limited to, WAG/WAP/WES/WET/WRT-series router models and Wireless-N access points and routers. Exploitation evidence was observed by the Shadowserver Foundation on 2025-02-06 UTC.

Source: CVE List, as of 30 Oct 2026. About the data.

What to do

Advisories and patches

The CVE record links no vendor advisory, patch or mitigation.

This summary is based on the CVE record as of 30 Oct 2026. Check the vendor's advisory before you act: affected versions and fixes can change.