How severe is CVE-2022-0734?

CVE-2022-0734 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2022-0734 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-0734?

CVE-2022-0734 primarily affects Zyxel Vpn100 Firmware. In total, 32 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-0734?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2022-0734 published?

CVE-2022-0734 was published on 2022-05-24 and last updated on 2026-06-17.

CVE-2022-0734

CVE-2022-0734 is a medium-severity vulnerability in Zyxel Vpn100 Firmware with a CVSS 3.x base score of 5.8. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
CVSS v2: 4.3
EPSS exploit prediction: 8% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Zyxel Vpn100 Firmware
Published: 2022-05-24
Last modified: 2026-06-17

Description

A cross-site scripting vulnerability was identified in the CGI program of Zyxel USG/ZyWALL series firmware versions 4.35 through 4.70, USG FLEX series firmware versions 4.50 through 5.20, ATP series firmware versions 4.35 through 5.20, and VPN series firmware versions 4.35 through 5.20, that could allow an attacker to obtain some information stored in the user's browser, such as cookies or session tokens, via a malicious script.

Frequently asked questions

What is CVE-2022-0734?: A cross-site scripting vulnerability was identified in the CGI program of Zyxel USG/ZyWALL series firmware versions 4.35 through 4.70, USG FLEX series firmware versions 4.50 through 5.20, ATP series firmware versions 4.35 through 5.20, and VPN series firmware versions 4.35 through 5.20, that could allow an attacker to obtain some information stored in the user's browser, such as cookies or session tokens, via a malicious script.
How severe is CVE-2022-0734?: CVE-2022-0734 has a CVSS 3.x base score of 5.8, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2022-0734 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-0734?: CVE-2022-0734 primarily affects Zyxel Vpn100 Firmware. In total, 32 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-0734?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2022-0734 published?: CVE-2022-0734 was published on 2022-05-24 and last updated on 2026-06-17.

References

https://www.zyxel.com/support/multiple-vulnerabilities-of-firewalls-AP-controllers-and-APs.shtml

Affected products (32)

cpe:2.3:o:zyxel:vpn100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn1000_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vpn50_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp100w_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp700_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:atp800_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_110_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_1100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_1900_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_20w_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_20w-vpn_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_2200-vpn_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_310_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_40_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_40w_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_60_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_60w_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg20_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg210_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg2200_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg300_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:usg310_firmware:*:*:*:*:*:*:*:*

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