CVE-2025-8820 in RE6250
Summary
by MITRE • 08/11/2025
A vulnerability was determined in Linksys RE6250, RE6300, RE6350, RE6500, RE7000 and RE9000 up to 20250801. This vulnerability affects the function wirelessBasic of the file /goform/wirelessBasic. The manipulation of the argument submit_SSID1 leads to stack-based buffer overflow. The attack can be initiated 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.
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Analysis
by VulDB Data Team • 09/04/2025
This vulnerability exists in multiple Linksys router models including RE6250, RE6300, RE6350, RE6500, RE7000, and RE9000 firmware versions up to 20250801. The flaw is located within the wirelessBasic function of the /goform/wirelessBasic file which handles wireless network configuration parameters. The specific vulnerability arises from improper input validation when processing the submit_SSID1 argument, creating a stack-based buffer overflow condition that can be exploited through remote network access. This represents a critical security flaw that allows attackers to potentially execute arbitrary code on affected devices, compromising the entire network infrastructure.
The technical implementation of this vulnerability follows a classic stack-based buffer overflow pattern where insufficient bounds checking allows an attacker to overwrite adjacent memory locations on the stack. When the submit_SSID1 parameter is manipulated beyond the allocated buffer size, it overflows into adjacent stack variables and potentially into return addresses, enabling arbitrary code execution. This type of vulnerability is classified as CWE-121 Stack-based Buffer Overflow, which is a well-documented and dangerous class of vulnerabilities in embedded systems and network devices. The attack vector is remote, meaning no physical access or local network presence is required to exploit this flaw, making it particularly dangerous for widespread deployment.
The operational impact of this vulnerability extends beyond simple device compromise as it affects consumer-grade routers that serve as primary network gateways for residential and small business environments. Successful exploitation could allow attackers to gain full administrative control over affected routers, potentially enabling man-in-the-middle attacks, DNS hijacking, traffic interception, and lateral network movement. The fact that the exploit has been publicly disclosed and is actively being used in the wild significantly increases the risk to affected users who may not have updated their firmware. According to ATT&CK framework, this vulnerability maps to T1059 Command and Scripting Interpreter and T1071.004 Application Layer Protocol DNS, as attackers could leverage compromised devices to conduct DNS tunneling or execute commands through the router's web interface.
Organizations and individuals should immediately implement mitigations including firmware updates from Linksys if available, network segmentation to isolate affected devices, and monitoring for unusual network activity that might indicate exploitation attempts. Network administrators should consider implementing firewall rules to restrict access to the router's web management interface from untrusted networks and disable unnecessary services. The lack of vendor response to early disclosure attempts compounds the severity of this issue, as users have no assurance of future patches or security updates for these devices. Given the public availability of exploitation tools and the widespread deployment of these router models, proactive network defense measures are essential to protect against potential compromise and maintain network security posture.