CVE-2020-26728

Name: CVE-2020-26728
Creator: NVD / NIST
Published: 2022-02-11T19:15:08.027+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 3.53%

Last modified Jun 17, 2026

CVE-2020-26728 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. A vulnerability was discovered in Tenda AC9 v3.0 V15.03.06.42_multi and Tenda AC9 V1.0 V15.03.05.19(6318)_CN which allows for remote code execution via shell metacharacters in the guestuser field to the __fastcall function with a POST request.. EPSS estimates a 3.53% chance of exploitation in the next 30 days.

Description

A vulnerability was discovered in Tenda AC9 v3.0 V15.03.06.42_multi and Tenda AC9 V1.0 V15.03.05.19(6318)_CN which allows for remote code execution via shell metacharacters in the guestuser field to the __fastcall function with a POST request.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

3.53%

87.8th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Tenda	Ac9 Firmware	15.03.06.42_multi
Tenda	Ac9 Firmware	15.03.05.19\(6318\)_cn

References

https://github.com/Lyc-heng/Router/blob/main/Tenda/rce1.mdBroken Link
https://github.com/Lyc-heng/routers/blob/a80b30bccfc9b76f3a4868ff28ad5ce2e0fca180/routers/rce1.mdExploit, Third Party Advisory
https://github.com/Lyc-heng/routers/blob/main/routers/rce1.mdExploit, Third Party Advisory
https://github.com/Lyc-heng/Router/blob/main/Tenda/rce1.mdBroken Link
https://github.com/Lyc-heng/routers/blob/a80b30bccfc9b76f3a4868ff28ad5ce2e0fca180/routers/rce1.mdExploit, Third Party Advisory
https://github.com/Lyc-heng/routers/blob/main/routers/rce1.mdExploit, Third Party Advisory

Timeline

Published: Feb 11, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-26728?

How severe is CVE-2020-26728?

CVE-2020-26728 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 3.53% probability of exploitation in the next 30 days.

How do I fix CVE-2020-26728?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-26728?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST