How severe is CVE-2021-45736?

CVE-2021-45736 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-45736 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-45736?

CVE-2021-45736 affects Totolink X5000r Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-45736?

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

When was CVE-2021-45736 published?

CVE-2021-45736 was published on 2022-02-04 and last updated on 2026-06-17.

CVE-2021-45736

CVE-2021-45736 is a high-severity vulnerability in Totolink X5000r Firmware with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 1% (64th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Totolink X5000r Firmware
Published: 2022-02-04
Last modified: 2026-06-17

Description

TOTOLINK X5000R v9.1.0u.6118_B20201102 was discovered to contain a stack overflow in the function setL2tpServerCfg. This vulnerability allows attackers to cause a Denial of Service (DoS) via the eip, sip, server parameters.

Frequently asked questions

What is CVE-2021-45736?: TOTOLINK X5000R v9.1.0u.6118_B20201102 was discovered to contain a stack overflow in the function setL2tpServerCfg. This vulnerability allows attackers to cause a Denial of Service (DoS) via the eip, sip, server parameters.
How severe is CVE-2021-45736?: CVE-2021-45736 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-45736 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-45736?: CVE-2021-45736 affects Totolink X5000r Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-45736?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-45736 published?: CVE-2021-45736 was published on 2022-02-04 and last updated on 2026-06-17.

References

https://github.com/pjqwudi/my_vuln/blob/main/totolink/vuln_9/9.md

Affected products (1)

cpe:2.3:o:totolink:x5000r_firmware:9.1.0u.6118_b20201102:*:*:*:*:*:*:*

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