Medium severity · published May 24, 2022
CVE-2021-42659
There is a buffer overflow vulnerability in the Web server httpd of the router in Tenda router devices such as Tenda AC9 V1.0 V15.03.02.19(6318) and Tenda AC9 V3.0…
6.5
CVSS
0.8%
EPSS
No
On KEV
Description
There is a buffer overflow vulnerability in the Web server httpd of the router in Tenda router devices such as Tenda AC9 V1.0 V15.03.02.19(6318) and Tenda AC9 V3.0 V15.03.06.42_multi. When setting the virtual service, the httpd program will crash and exit when the super-long list parameter occurs.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 57% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AF
Ac9 Firmware · Tenda
15.03.05.19(6318); 15.03.06.42_multi · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-42659
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-42659
Exploit
https://github.com/Lyc-heng/routers/blob/main/routers/stack4.md
Third Party Advisory
https://www.cnvd.org.cn/flaw/show/CNVD-2021-24948
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