CVE-2021-27705

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.

CVSS v3 9.8 CRITICAL
CVSS v2.0 7.5 HIGH

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://hackmd.io/Zb7lfFaNR0ScpaTssECFbg	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:tenda:g1_firmware:v15.11.0.17\(9502\)_cn:*:*:*:*:*:*:*

cpe:2.3:h:tenda:g1:-:*:*:*:*:*:*:*

Configuration 2 (hide)

AND

cpe:2.3:o:tenda:g3_firmware:v15.11.0.17\(9502\)_cn:*:*:*:*:*:*:*

cpe:2.3:h:tenda:g3:-:*:*:*:*:*:*:*

History

20 Apr 2021, 21:43

Type	Values Removed	Values Added
CPE		cpe:2.3:o:tenda:g3_firmware:v15.11.0.17\(9502\)_cn:::::::* cpe:2.3:h:tenda:g3:-:::::::* cpe:2.3:h:tenda:g1:-:::::::* cpe:2.3:o:tenda:g1_firmware:v15.11.0.17\(9502\)_cn:::::::*
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : 7.5 v3 : 9.8
References	~~(MISC) https://hackmd.io/Zb7lfFaNR0ScpaTssECFbg -~~	(MISC) https://hackmd.io/Zb7lfFaNR0ScpaTssECFbg - Exploit, Third Party Advisory
CWE		CWE-120

14 Apr 2021, 15:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2021-04-14 15:15

Updated : 2023-12-10 13:55

NVD link : CVE-2021-27705

Mitre link : CVE-2021-27705

CVE.ORG link : CVE-2021-27705

JSON object : View

Products Affected

tenda

g3
g1
g3_firmware
g1_firmware

CWE

CWE-120

Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')

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