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Fencer Intel
critical 9.8

CVE-2021-27710 json

Command Injection in TOTOLINK X5000R router with firmware v9.1.0u.6118_B20201102, and TOTOLINK A720R router with firmware v4.1.5cu.470_B202…

published 5y ago modified 4mo ago also EUVD-2021-14452

cvss
9.8
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
7.9%
EPSS 7.9% chance of exploitation in 30 days, percentile 94%
public exploits
0
none known

Summary

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.

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Exploit prediction

7.91% chance of exploitation in the next 30 days, higher than 94% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • hackmd.io https://hackmd.io/KjXzQdjDRjOuRjoZZXQo_A referenced PoC, tagged "exploit" by a source, unverified
  • hackmd.io https://hackmd.io/Hy3oVgtcQiuqAtv9FdylHw referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 10.0 AV:N/AC:L/Au:N/C:C/I:C/A:C

Classification

Weakness
  • CWE-78 Improper Neutralization of Special Elements used in an OS Command

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.