CVE-2025-6752: Linksys WRT1900ACS · Stack-based Buffer Overflow
Affects Linksys WRT1900ACSSource CVE Database V5
Not known to be exploited · CVSS 8.7 High.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 1.1% chance of exploitation in 30 days – higher than 66% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 27 Jun 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Linksys WRT1900ACS | Affected
| Fixed in– |
AI-suggested
Immediate mitigation steps include: 1) Identifying and inventorying all affected Linksys router models within the organization’s network. 2) Restricting access to the UPnP service, especially the /upnp/control/Layer3Forwarding endpoint, by disabling UPnP entirely if not required, or by implementing strict firewall rules to block external and untrusted internal access to the router’s management interfaces. 3) Segregating network segments to limit exposure of vulnerable devices from untrusted networks or users. 4) Monitoring network traffic for unusual or suspicious UPnP requests that could indicate exploitation attempts. 6) Employing network intrusion detection/prevention systems (IDS/IPS) with signatures for this vulnerability or related exploit attempts. 7) Educating IT staff and users about the risks and signs of router compromise. 8) Regularly backing up router configurations and preparing incident response plans for potential compromise scenarios. These measures go beyond generic advice by focusing on UPnP service restriction, network segmentation, and active monitoring tailored to this specific vulnerability.
Description
A vulnerability has been found in Linksys WRT1900ACS, EA7200, EA7450 and EA7500 up to 20250619 and classified as critical. This vulnerability affects the function SetDefaultConnectionService of the file /upnp/control/Layer3Forwarding of the component IGD. The manipulation of the argument NewDefaultConnectionService 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.