How severe is CVE-2021-42890?

CVE-2021-42890 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-2021-42890 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42890?

CVE-2021-42890 affects Totolink Ex1200t Firmware. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42890?

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-2021-42890 published?

CVE-2021-42890 was published on 2022-06-03 and last updated on 2026-06-17.

CVE-2021-42890

CVE-2021-42890 is a critical-severity vulnerability in Totolink Ex1200t 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-78.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (78th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-78
Affected product: Totolink Ex1200t Firmware
Published: 2022-06-03
Last modified: 2026-06-17

Description

TOTOLINK EX1200T V4.1.2cu.5215 contains a remote command injection vulnerability in function NTPSyncWithHost of the file system.so which can control hostTime to attack.

Frequently asked questions

What is CVE-2021-42890?: TOTOLINK EX1200T V4.1.2cu.5215 contains a remote command injection vulnerability in function NTPSyncWithHost of the file system.so which can control hostTime to attack.
How severe is CVE-2021-42890?: CVE-2021-42890 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-2021-42890 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (78th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42890?: CVE-2021-42890 affects Totolink Ex1200t Firmware. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42890?: 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-2021-42890 published?: CVE-2021-42890 was published on 2022-06-03 and last updated on 2026-06-17.

References

https://github.com/p1Kk/vuln/blob/main/totolink_ex1200t_hosttime_rce.md

Affected products (1)

cpe:2.3:o:totolink:ex1200t_firmware:4.1.2cu.5215:*:*:*:*:*:*:*

More vulnerabilities in Totolink Ex1200t Firmware

CVE-2025-51451 — Critical (CVSS 9.8): In TOTOLINK EX1200T firmware 4.1.2cu.5215, an attacker can bypass login by sending a specific request through…
CVE-2025-5600 — Critical (CVSS 9.8): A vulnerability, which was classified as critical, has been found in TOTOLINK EX1200T 4.1.2cu.5232_B20210713. This…
CVE-2025-28039 — Critical (CVSS 9.8): TOTOLINK EX1200T V4.1.2cu.5232_B20210713 was found to contain a pre-auth remote command execution vulnerability in the…
CVE-2025-28038 — Critical (CVSS 9.8): TOTOLINK EX1200T V4.1.2cu.5232_B20210713 was found to contain a pre-auth remote command execution vulnerability in the…
CVE-2023-52032 — Critical (CVSS 9.8): TOTOlink EX1200T V4.1.2cu.5232_B20210713 was discovered to contain a remote command execution (RCE) vulnerability via…
CVE-2021-42888 — Critical (CVSS 9.8): TOTOLINK EX1200T V4.1.2cu.5215 contains a remote command injection vulnerability in function setLanguageCfg of the file…

All CVEs affecting Totolink Ex1200t Firmware →

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