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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.83%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 2.83% probability · 87th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-120
- Affected
- tenda/g1 firmware · tenda/g3 firmware
- Source
- cve@mitre.org
EPSS 2.8% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://hackmd.io/U7OVgYIuRcOKV7SW5-euHwExploit, Third Party Advisory
- https://hackmd.io/U7OVgYIuRcOKV7SW5-euHwExploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.