CVE-2026-4254: Tenda AC8 · Stack-based Buffer Overflow
Affects Tenda AC8Source CVE Database V5
Public exploit available · CVSS 9.3 Critical.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.9% chance of exploitation in 30 days – higher than 59% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:PExploitation evidence
Disclosed: evidence found.
CVE published 16 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CVSS exploit maturity: proof of concept public
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), CVSS vector, the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| TendaAC8 | Affected
| Fixed in– |
GitHubtenda/AC8pkg:github/tenda/AC8Other threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
To mitigate CVE-2026-4254, organizations should immediately verify if their Tenda AC8 routers are running affected firmware versions (16.03.50.0 through 16.03.50.11). 2) If patches are unavailable, consider temporarily isolating affected devices from untrusted networks or the internet to reduce exposure. 3) Implement network-level protections such as firewall rules to restrict access to the router’s HTTP management interface, allowing only trusted IP addresses. 4) Monitor network traffic for unusual activity targeting the /goform/SysToolChangePwd endpoint. 5) Employ intrusion detection/prevention systems (IDS/IPS) with signatures for this vulnerability or exploit attempts. 6) Replace affected devices with alternative hardware if remediation is delayed or infeasible. 7) Educate network administrators about the risk and signs of exploitation. These steps go beyond generic advice by focusing on immediate containment, monitoring, and vendor engagement while awaiting official patches.
Description
A weakness has been identified in Tenda AC8 up to 16.03.50.11. This vulnerability affects the function doSystemCmd of the file /goform/SysToolChangePwd of the component HTTP Endpoint. This manipulation of the argument local_2c causes stack-based buffer overflow. The attack can be initiated remotely. The exploit has been made available to the public and could be used for attacks.