vulntracker.iovulntracker.io
© 2026 vulntracker.io

CVE-2021-27705

CRITICAL
9.8
CVSS Score
Published: April 14, 2021 at 02:52 PM UTC
Updated: June 17, 2026 at 03:45 AM UTC
4 products affected across 1 vendorG3 FirmwareG1 FirmwareTenda G3

Using N/A by N/A?

Get instant alerts when new vulnerabilities affect N/A - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Start FreeSign In
Severity
CRITICAL9.8
Exploit prediction
EPSS 3%

Description

Buffer Overflow in Tenda G1 and G3 routers with firmware v15.11.0.17(9502)_CN allows remote attackers to execute arbitrary code via a crafted action/"qosIndex "request. This occurs because the "formQOSRuleDel" function directly passes the parameter "qosIndex" to strcpy without limit.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

G1 Firmware· Tenda
95%
15.11.0.17(9502)_cn
tenda-g1 (same device)
G3 Firmware· Tenda
95%
15.11.0.17(9502)_cn
G1· Tendadevice
80%
All versions
Tenda G3· Tendadevice
80%
All versions

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

x_refsource_MISCExploitThird Party Advisory
Source: [email protected]
https://hackmd.io/Zb7lfFaNR0ScpaTssECFbg

CVSS

9.8CRITICAL[email protected]
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-120

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Create accountSign in
Free plan, no card