How severe is CVE-2021-43636?

CVE-2021-43636 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-2021-43636 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43636?

CVE-2021-43636 affects Totolink T10 V2 Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43636?

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-2021-43636 published?

CVE-2021-43636 was published on 2022-03-25 and last updated on 2026-06-17.

CVE-2021-43636

CVE-2021-43636 is a critical-severity vulnerability in Totolink T10 V2 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: 7.5
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-120
Affected product: Totolink T10 V2 Firmware
Published: 2022-03-25
Last modified: 2026-06-17

Description

Two Buffer Overflow vulnerabilities exists in T10 V2_Firmware V4.1.8cu.5207_B20210320 in the http_request_parse function when processing host data in the HTTP request process.

Frequently asked questions

What is CVE-2021-43636?: Two Buffer Overflow vulnerabilities exists in T10 V2_Firmware V4.1.8cu.5207_B20210320 in the http_request_parse function when processing host data in the HTTP request process.
How severe is CVE-2021-43636?: CVE-2021-43636 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-2021-43636 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43636?: CVE-2021-43636 affects Totolink T10 V2 Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43636?: 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-2021-43636 published?: CVE-2021-43636 was published on 2022-03-25 and last updated on 2026-06-17.

References

https://note.youdao.com/s/918vCBNT

Affected products (1)

cpe:2.3:o:totolink:t10_v2_firmware:4.1.8cu.5207_b20210320:*:*:*:*:*:*:*

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