CVE-2021-35027
CVE-2021-35027 is a high-severity vulnerability in Zyxel Zywall Vpn2s 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. The underlying weakness is classified as CWE-22.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (78th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-22
- Affected product: Zyxel Zywall Vpn2s Firmware
- Published:
- Last modified:
Description
A directory traversal vulnerability in the web server of the Zyxel VPN2S firmware version 1.12 could allow a remote attacker to gain access to sensitive information.
Frequently asked questions
- What is CVE-2021-35027?
- A directory traversal vulnerability in the web server of the Zyxel VPN2S firmware version 1.12 could allow a remote attacker to gain access to sensitive information.
- How severe is CVE-2021-35027?
- CVE-2021-35027 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 high, integrity none, and availability none.
- Is CVE-2021-35027 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-2021-35027?
- CVE-2021-35027 affects Zyxel Zywall Vpn2s Firmware. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-35027?
- 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-2021-35027 published?
- CVE-2021-35027 was published on 2021-09-29 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:o:zyxel:zywall_vpn2s_firmware:1.12\(abln.0\)c0:*:*:*:*:*:*:*
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