CVE-2025-14134 Overview
CVE-2025-14134 is a stack-based buffer overflow affecting multiple Linksys wireless range extender models, including the RE6500, RE6250, RE6300, RE6350, RE7000, and RE9000. The flaw resides in the RE2000v2Repeater_get_wireless_clientlist_setClientsName function within mod_form.so. An authenticated remote attacker can manipulate the clientsname_0 argument to overflow a fixed-size stack buffer. The exploit has been publicly disclosed, and the vendor did not respond to disclosure attempts. The weakness is classified under CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer.
Critical Impact
Remote attackers with low privileges can corrupt the stack of the device's web management service, enabling potential code execution or denial of service across multiple Linksys range extender models.
Affected Products
- Linksys RE6500 firmware 1.0.013.001 and RE6250 firmware 1.0.04.001
- Linksys RE6300 firmware 1.2.07.001 and RE6350 firmware 1.0.04.001
- Linksys RE7000 firmware 1.1.05.003 and RE9000 firmware 1.0.04.002
Discovery Timeline
- 2025-12-06 - CVE-2025-14134 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-14134
Vulnerability Analysis
The vulnerability exists in the RE2000v2Repeater_get_wireless_clientlist_setClientsName function exported by mod_form.so, a shared library used by the Linksys range extender web management interface. The function processes the clientsname_0 parameter, which represents a wireless client name. Input length is not validated before the value is copied into a fixed-size stack buffer.
When an attacker supplies an oversized clientsname_0 value, the copy operation writes past the buffer boundary and overwrites adjacent stack data. This includes saved return addresses and frame pointers on MIPS or ARM-based router builds. The vulnerability falls under [CWE-119] memory boundary errors. Successful exploitation can lead to arbitrary code execution within the context of the web service process, which typically runs with elevated privileges on consumer network devices.
Root Cause
The root cause is the absence of bounds checking on the clientsname_0 HTTP parameter before it is copied into a stack-resident buffer. The handler in mod_form.so trusts client-supplied data without enforcing a maximum length. There is no length validation, no safe string copy primitive, and no stack canary protection on the affected firmware images.
Attack Vector
An attacker with network access to the device's HTTP management interface and valid low-privilege credentials can trigger the overflow. The attacker submits a crafted HTTP request that invokes the wireless client list handler with an overlong clientsname_0 value. If the management interface is exposed to a wider network segment or the internet, the attack surface increases. Public proof-of-concept material is available through GitHub Vulnerability Documentation and VulDB #334523.
No verified exploit code is reproduced here. Refer to the linked references for the technical proof-of-concept.
Detection Methods for CVE-2025-14134
Indicators of Compromise
- HTTP POST or GET requests to range extender management endpoints containing abnormally long clientsname_0 parameter values
- Unexpected reboots, watchdog resets, or service crashes of the embedded web daemon on affected Linksys devices
- Outbound connections from a range extender to unfamiliar IP addresses after suspicious management traffic
Detection Strategies
- Inspect HTTP request bodies and query strings destined for range extender admin interfaces for clientsname_0 parameters exceeding typical SSID client name lengths
- Correlate authentication events to the device admin portal with subsequent service crashes or configuration changes
- Monitor for repeated failed logins followed by malformed requests targeting mod_form.so handlers
Monitoring Recommendations
- Forward router and firewall syslog data to a centralized logging platform to identify anomalous traffic toward management VLANs
- Place range extenders on isolated management network segments and alert on any inbound HTTP traffic from user or guest segments
- Track device uptime metrics through SNMP or vendor APIs to identify unexpected restarts that may indicate exploitation attempts
How to Mitigate CVE-2025-14134
Immediate Actions Required
- Restrict access to the range extender web management interface to a dedicated management subnet and block exposure to untrusted networks
- Disable remote administration features on all affected RE-series devices until a vendor patch is available
- Rotate administrative credentials and enforce strong, unique passwords given that exploitation requires low-privilege authentication
Patch Information
No vendor patch is currently available. According to the disclosure record, Linksys was contacted early but did not respond. Monitor the Linksys Official Website and VulDB #334523 for any future firmware updates addressing this issue.
Workarounds
- Replace affected end-of-support range extenders with current-generation hardware that receives active security maintenance
- Place the device behind a network firewall that filters inbound HTTP and HTTPS traffic to the extender's management port
- Disable the wireless client list feature in the administrative UI if the configuration option is available on the firmware version in use
- Segment IoT and consumer network equipment away from sensitive corporate assets to limit lateral movement after compromise
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
