Linksys Ignored Contact on CVE-2026-108892, Leaving E1700 Router to Critical CVSS 9.3 Remote Overflow
A critical vulnerability in Linksys E1700 firmware allows remote attackers to trigger a stack-based buffer overflow via the MAC filter component.
Key points
- CVE-2026-108892 affects Linksys E1700 firmware version 1.0.0.4.003.
- The flaw is a remotely exploitable stack-based buffer overflow rated CVSS 9.3 or 10.
- Linksys did not respond to early contact regarding this public disclosure.
Linksys E1700 wireless routers running firmware version 1.0.0.4.003 contain a critical remote vulnerability. Security databases list this flaw as CVE-2026-108892, which allows attackers to exploit a stack-based buffer overflow in the device’s MAC filtering functionality remotely.
At a glance
- CVE
- CVE-2026-108892
- Product
- Linksys E1700
- CVSS
- 10 Critical
- Weakness
- stack-based buffer overflow
- Exploited
- No known exploitation
The vulnerability resides in the ssid1MACFilter function within the /goform/ssid1MACFilter file. According to the National Vulnerability Database, manipulating the newap_text_%d argument triggers the overflow. This weakness is classified under CWE-121 and CWE-119, indicating improper memory management associated with the stack-based buffer overflow.
Severity and Exposure
The National Vulnerability Database assigns this flaw a CVSS score of 9.3, labeling it critical. Some records also list a CVSS score of 10, the highest possible severity rating. Both scores reflect the critical nature of the vulnerability as determined by the database.
The attack vector is remote, meaning an attacker can initiate the exploit remotely. The flaw affects the Mac Filter component specifically, which is part of the firmware version 1.0.0.4.003. This component handles MAC filtering operations on the device.
Vendor Response and Status
Linksys was contacted early in the disclosure process regarding this security issue. According to the vulnerability record, the vendor did not respond in any way to these initial outreach attempts. As of this report, there is no confirmed patch or security update available for firmware version 1.0.0.4.003.
The lack of vendor response leaves users of this specific firmware version exposed to potential compromise. The public nature of the exploit code means the exploit has been publicly disclosed and may be utilized. Administrators should monitor for any official statements from Linksys regarding remediation.
What should you do?
Users running Linksys E1700 routers should verify their current firmware version immediately. If the device is running version 1.0.0.4.003, it is vulnerable to this remote stack overflow. Network administrators should isolate these devices from untrusted networks to reduce the attack surface while waiting for a vendor response.
What to do and how to stay safe: Linksys
- Check the firmware version on all Linksys E1700 devices to confirm if they run 1.0.0.4.003.
- Disable the MAC filter feature on vulnerable devices if it is not strictly required for security.
- Monitor network traffic for unusual activity originating from or targeting the router’s management interface.
- Wait for an official security advisory or patch from Linksys before applying any unofficial fixes.
Step-by-step guide: Risk Based Vulnerability Management: Prioritize Fixes by Actual Threat
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-108892?
It is a critical stack-based buffer overflow vulnerability in Linksys E1700 firmware version 1.0.0.4.003 that affects the MAC filter component.
Is there a patch available for this flaw?
No, the vendor did not respond to early contact, and no fix has been confirmed yet.
How severe is this vulnerability?
It is rated critical with a CVSS score of 9.3 or 10, allowing remote exploitation.
