TI-2021-11772 Aliases CVE-2021-31755 GHSA-539c-2w6v-9rwx

An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN.

CRITICAL 100Exploited in the wildCWE-787Published 2021-05-07 · Updated 2025-10-21

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.

Summary

An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. A stack buffer overflow vulnerability in /goform/setmac allows attackers to execute arbitrary code on the system via a crafted post request.

Why it matters now

Exploitation Active In CISA KEV since 2021-11-03CISA due date 2021-11-17

EPSS 0.86511 99th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Active
Automatable: Yes
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:o:tenda:ac11_firmware::::::::	up to 02.03.01.104_cn	Vulnerable	Tenda
cpe:2.3:h:tenda:ac11:-:::::::*	not specified by NVD	Running on	Tenda

cpe:2.3:o:tenda:ac11_firmware:*:*:*:*:*:*:*:* Versions up to 02.03.01.104_cn Vulnerable ·Tenda
cpe:2.3:h:tenda:ac11:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Tenda

Remediation

No fixed version listed by the sources yet.

Timeline

2021-11-03 Added to CISA KEV
2026-10-02 Threatist record created from CVE-2021-31755
2026-10-03 Alias added: GHSA-539c-2w6v-9rwx

References

Exploit 1

https://github.com/Yu3H0/IoT_CVE/tree/main/Tenda/CVE_3

TI-2021-11775 An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. CVSS 3.1CRITICAL 9.8
TI-2021-11774 An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. CVSS 3.1CRITICAL 9.8
TI-2021-11773 An issue was discovered on Tenda AC11 devices with firmware through 02.03.01.104_CN. CVSS 3.1CRITICAL 9.8
TI-2021-21157 Tenda AC Series Router AC11_V02.03.01.104_CN was discovered to contain a stack buffer… CVSS 3.1CRITICAL 9.8
TI-2021-21141 Tenda AC Series Router AC11_V02.03.01.104_CN was discovered to contain a stack buffer… CVSS 3.1CRITICAL 9.8
TI-2021-21140 Tenda AC Series Router AC11_V02.03.01.104_CN was discovered to contain a stack buffer… CVSS 3.1CRITICAL 9.8

See all 8 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences