Critical severity · published Apr 14, 2021
CVE-2021-27708
Command Injection in TOTOLINK X5000R router with firmware v9.1.0u.6118_B20201102, and TOTOLINK A720R router with firmware v4.1.5cu.470_B20200911 allows remote attackers to execute…
9.8
CVSS
7.6%
EPSS
No
On KEV
Description
Command Injection in TOTOLINK X5000R router with firmware v9.1.0u.6118_B20201102, and TOTOLINK A720R router with firmware v4.1.5cu.470_B20200911 allows remote attackers to execute arbitrary OS commands by sending a modified HTTP request. This occurs because the function executes glibc's system function with untrusted input. In the function, "command" parameter is directly passed to the attacker, allowing them to control the "command" field to attack the OS.
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)7.6% · higher than 95% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AF
A720r Firmware · Totolink
4.1.5cu.470_b20200911 · source: NVD
XF
X5000r Firmware · Totolink
9.1.0u.6118_b20201102 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-27708
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-27708
Exploit
https://hackmd.io/7FtB06f-SJ-SCfkMYcXYxA
Exploit
https://hackmd.io/mDgIBvoxSPCZrZiZjfQGhw
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