CVE-2021-27710

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 7.9% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-04-14 · updated 2026-06-17
Weakness: CWE-78

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, "ip" parameter is directly passed to the attacker, allowing them to control the "ip" field to attack the OS.

Affected products

TOTOLINK A720R: 4.1.5cu.470_b20200911
TOTOLINK X5000R: 9.1.0u.6118_b20201102

References

https://hackmd.io/Hy3oVgtcQiuqAtv9FdylHw
https://hackmd.io/KjXzQdjDRjOuRjoZZXQo_A
https://hackmd.io/Hy3oVgtcQiuqAtv9FdylHw
https://hackmd.io/KjXzQdjDRjOuRjoZZXQo_A

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