How severe is CVE-2021-43711?

CVE-2021-43711 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-43711 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 38% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43711?

CVE-2021-43711 affects Totolink Ex200 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43711?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-43711 published?

CVE-2021-43711 was published on 2022-01-04 and last updated on 2026-06-17.

CVE-2021-43711

CVE-2021-43711 is a critical-severity vulnerability in Totolink Ex200 Firmware with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 38% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-77.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 38% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-77
Affected product: Totolink Ex200 Firmware
Published: 2022-01-04
Last modified: 2026-06-17

Description

The downloadFlile.cgi binary file in TOTOLINK EX200 V4.0.3c.7646_B20201211 has a command injection vulnerability when receiving GET parameters. The parameter name can be constructed for unauthenticated command execution.

Frequently asked questions

What is CVE-2021-43711?: The downloadFlile.cgi binary file in TOTOLINK EX200 V4.0.3c.7646_B20201211 has a command injection vulnerability when receiving GET parameters. The parameter name can be constructed for unauthenticated command execution.
How severe is CVE-2021-43711?: CVE-2021-43711 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-43711 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 38% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43711?: CVE-2021-43711 affects Totolink Ex200 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43711?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-43711 published?: CVE-2021-43711 was published on 2022-01-04 and last updated on 2026-06-17.

References

https://github.com/doudoudedi/ToTolink_EX200_Cmmand_Execute/blob/main/ToTolink%20EX200%20Comand%20Injection2.md

Affected products (1)

cpe:2.3:o:totolink:ex200_firmware:4.0.3c.7646_b20201211:*:*:*:*:*:*:*

More vulnerabilities in Totolink Ex200 Firmware

CVE-2024-31810 — Critical (CVSS 9.8): TOTOLINK EX200 V4.0.3c.7646_B20201211 was discovered to contain a hardcoded password for root at /etc/shadow.sample.
CVE-2024-31807 — Critical (CVSS 9.8): TOTOLINK EX200 V4.0.3c.7646_B20201211 was discovered to contain a remote code execution (RCE) vulnerability via the…
CVE-2024-31815 — Critical (CVSS 9.1): In TOTOLINK EX200 V4.0.3c.7314_B20191204, an attacker can obtain the configuration file without authorization through…
CVE-2024-7336 — High (CVSS 8.8): A vulnerability classified as critical was found in TOTOLINK EX200 4.0.3c.7646_B20201211. Affected by this…
CVE-2024-7335 — High (CVSS 8.8): A vulnerability classified as critical has been found in TOTOLINK EX200 4.0.3c.7646_B20201211. Affected is the function…
CVE-2024-31814 — High (CVSS 8.8): TOTOLINK EX200 V4.0.3c.7646_B20201211 allows attackers to bypass login through the Form_Login function.

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