Cyber Resilience

CVE-2025-8818

LowPublic PoC

Published: 10 August 2025

Published
10 August 2025
Modified
29 April 2026
KEV Added
Patch
CVSS Score v4 2.1 CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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
EPSS Score 0.0415 88.9th percentile
Risk Priority 7 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-8818 is a low-severity Command Injection (CWE-77) vulnerability in Linksys Re6250 Firmware. Its CVSS base score is 2.1 (Low).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 11.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and AC-6 (Least Privilege).

Deeper analysis

A vulnerability has been identified in multiple Linksys Wi-Fi range extender models including the RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000 running firmware up to 20250801. The issue resides in the setDFSSetting function within the /goform/setLan endpoint, where unsanitized input to the lanNetmask and lanIp parameters permits operating system command injection, corresponding to CWE-77 and CWE-78.

An authenticated remote attacker with low privileges can supply crafted values to these parameters and execute arbitrary commands on the device. The attack requires no user interaction and can be launched over the network, resulting in limited impacts to confidentiality, integrity, and availability as reflected in the CVSS 2.1 rating. A functional proof-of-concept has been published publicly.

The vendor was notified prior to disclosure but provided no response or patch. Public references include detailed exploit code and technical write-ups on GitHub along with entries in the Vuldb database. The associated EPSS score has remained flat at 0.0415 with no material increase since publication.

EU & UK References

Vulnerability details

A vulnerability has been found in Linksys RE6250, RE6300, RE6350, RE6500, RE7000 and RE9000 up to 20250801. Affected by this issue is the function setDFSSetting of the file /goform/setLan. The manipulation of the argument lanNetmask/lanIp leads to os command injection.…

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The attack may be launched remotely. The exploit has been disclosed to the public and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1202 Indirect Command Execution Stealth
Adversaries may abuse utilities that allow for command execution to bypass security restrictions that limit the use of command-line interpreters.
Why these techniques?

OS command injection via web interface parameters (lanNetmask/lanIp) in setDFSSetting enables exploitation of public-facing application (T1190), command and scripting interpreter execution (T1059, likely Unix Shell), and indirect command execution (T1202) on the Linksys range extender.

CVEs Like This One

CVE-2025-8830Same product: Linksys Re6250
CVE-2025-8823Same product: Linksys Re6250
CVE-2025-8828Same product: Linksys Re6250
CVE-2025-8825Same product: Linksys Re6250
CVE-2025-8829Same product: Linksys Re6250
CVE-2025-9575Same product: Linksys Re6250
CVE-2025-8827Same product: Linksys Re6250
CVE-2025-9244Same product: Linksys Re6250
CVE-2025-8821Same product: Linksys Re6250
CVE-2025-9247Same product: Linksys Re6250

Affected Assets

linksys
re6250 firmware
1.0.04.001
linksys
re6300 firmware
1.2.07.001
linksys
re6350 firmware
1.0.04.001
linksys
re6500 firmware
1.0.013.001
linksys
re9000 firmware
1.0.04.002
linksys
re7000 firmware
1.1.05.003

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires validation and sanitization of lanNetmask/lanIp inputs to the /goform/setLan endpoint, blocking the OS command injection vector.

prevent

Limits the privileges of authenticated web-interface accounts so that even successful injection yields only the low-impact effects described in the CVSS vector.

detect

Enables monitoring of setLan requests and anomalous command execution behavior on the extender, surfacing exploitation attempts against the disclosed PoC.

References