How severe is CVE-2023-7221?

CVE-2023-7221 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-2023-7221 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-7221?

CVE-2023-7221 affects Totolink T6 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-7221?

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.

Does CVE-2023-7221 have an EU (EUVD) identifier?

Yes. CVE-2023-7221 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-59402.

When was CVE-2023-7221 published?

CVE-2023-7221 was published on 2024-01-09 and last updated on 2026-06-17.

CVE-2023-7221

CVE-2023-7221 is a critical-severity vulnerability in Totolink T6 Firmware with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-120.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-59402
Weakness: CWE-120
Affected product: Totolink T6 Firmware
Published: 2024-01-09
Last modified: 2026-06-17

Description

A vulnerability was found in Totolink T6 4.1.9cu.5241_B20210923. It has been classified as critical. This affects the function main of the file /cgi-bin/cstecgi.cgi?action=login of the component HTTP POST Request Handler. The manipulation of the argument v41 leads to buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used. The associated identifier of this vulnerability is VDB-249855. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.

Frequently asked questions

What is CVE-2023-7221?: A vulnerability was found in Totolink T6 4.1.9cu.5241_B20210923. It has been classified as critical. This affects the function main of the file /cgi-bin/cstecgi.cgi?action=login of the component HTTP POST Request Handler. The manipulation of the argument v41 leads to buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used. The associated identifier of this vulnerability is VDB-249855. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
How severe is CVE-2023-7221?: CVE-2023-7221 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-2023-7221 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-7221?: CVE-2023-7221 affects Totolink T6 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-7221?: 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.
Does CVE-2023-7221 have an EU (EUVD) identifier?: Yes. CVE-2023-7221 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-59402.
When was CVE-2023-7221 published?: CVE-2023-7221 was published on 2024-01-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:totolink:t6_firmware:4.1.9cu.5241_b20210923:*:*:*:*:*:*:*

More vulnerabilities in Totolink T6 Firmware

CVE-2022-38828 — Critical (CVSS 9.8): TOTOLINK T6 V4.1.5cu.709_B20210518 is vulnerable to command injection via cstecgi.cgi
CVE-2022-38827 — Critical (CVSS 9.8): TOTOLINK T6 V4.1.5cu.709_B20210518 is vulnerable to Buffer Overflow via cstecgi.cgi
CVE-2022-38826 — Critical (CVSS 9.8): In TOTOLINK T6 V4.1.5cu.709_B20210518, there is an execute arbitrary command in cstecgi.cgi.
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