CVE-2021-4030
CVE-2021-4030 is a high-severity vulnerability in Zyxel Nbg6816 Firmware with a CVSS 3.x base score of 8.0. 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-352.
Key facts
- Severity: High (CVSS 3.x base score 8.0)
- CVSS v2: 6.8
- EPSS exploit prediction: 0% (35th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-352
- Affected product: Zyxel Nbg6816 Firmware
- Published:
- Last modified:
Description
A cross-site request forgery vulnerability in the HTTP daemon of the Zyxel ARMOR Z1/Z2 firmware could allow an attacker to execute arbitrary commands if they coerce or trick a local user to visit a compromised website with malicious scripts.
Frequently asked questions
- What is CVE-2021-4030?
- A cross-site request forgery vulnerability in the HTTP daemon of the Zyxel ARMOR Z1/Z2 firmware could allow an attacker to execute arbitrary commands if they coerce or trick a local user to visit a compromised website with malicious scripts.
- How severe is CVE-2021-4030?
- CVE-2021-4030 has a CVSS 3.x base score of 8.0, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-4030 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (35th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-4030?
- CVE-2021-4030 primarily affects Zyxel Nbg6816 Firmware. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-4030?
- 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-2021-4030 published?
- CVE-2021-4030 was published on 2022-02-24 and last updated on 2026-06-17.
References
Affected products (2)
- cpe:2.3:o:zyxel:nbg6816_firmware:1.00\(aawb.10\)c0:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:nbg6817_firmware:*:*:*:*:*:*:*:*
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