Critical severity · published Apr 14, 2021
CVE-2021-27707
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/"portMappingIndex "request
9.8
CVSS
2.8%
EPSS
No
On KEV
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/"portMappingIndex "request. This occurs because the "formDelPortMapping" function directly passes the parameter "portMappingIndex" to strcpy without limit.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.8% · higher than 87% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GF
G1 Firmware · Tenda
v15.11.0.17(9502)_cn · source: NVD
GF
G3 Firmware · Tenda
v15.11.0.17(9502)_cn · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27707
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27707
Exploit
https://hackmd.io/U7OVgYIuRcOKV7SW5-euHw
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