How severe is CVE-2021-35036?

CVE-2021-35036 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-35036 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-35036?

CVE-2021-35036 primarily affects Zyxel Ax7501-b0 Firmware. In total, 33 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-35036?

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

When was CVE-2021-35036 published?

CVE-2021-35036 was published on 2022-03-01 and last updated on 2026-06-17.

CVE-2021-35036

CVE-2021-35036 is a medium-severity vulnerability in Zyxel Ax7501-b0 Firmware with a CVSS 3.x base score of 6.5. 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-312.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 3.5
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-312
Affected product: Zyxel Ax7501-b0 Firmware
Published: 2022-03-01
Last modified: 2026-06-17

Description

A cleartext storage of information vulnerability in the Zyxel VMG3625-T50B firmware version V5.50(ABTL.0)b2k could allow an authenticated attacker to obtain sensitive information from the configuration file.

Frequently asked questions

What is CVE-2021-35036?: A cleartext storage of information vulnerability in the Zyxel VMG3625-T50B firmware version V5.50(ABTL.0)b2k could allow an authenticated attacker to obtain sensitive information from the configuration file.
How severe is CVE-2021-35036?: CVE-2021-35036 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-35036 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-35036?: CVE-2021-35036 primarily affects Zyxel Ax7501-b0 Firmware. In total, 33 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-35036?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-35036 published?: CVE-2021-35036 was published on 2022-03-01 and last updated on 2026-06-17.

References

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-cleartext-storage-of-information-vulnerability

Affected products (33)

cpe:2.3:o:zyxel:ax7501-b0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:dx3301-t0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:dx5401-b0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:emg3525-t50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:emg5523-t50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:emg5723-t50k_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:ep240p_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:ex5401-b0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:ex5501-b0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte3301-plus_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte5388-m804_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte5388-s905_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte5398-m904_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte7240-m403_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte7461-m602_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte7480-m804_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte7480-s905_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte7485-s905_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:lte7490-m804_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:nr5101_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:nr7101_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:nr7102_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:pm7300-t0_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:pmg5317-t20b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:pmg5617-t20b2_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:pmg5617ga_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:pmg5622ga_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3625-t50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3927-t50k_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8623-t50b_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg8825-t50k_firmware:*:*:*:*:*:*:*:*
cpe:2.3:o:zyxel:vmg3625-t50b_firmware:*:*:*:*:central_america:*:*:*
cpe:2.3:o:zyxel:vmg3625-t50b_firmware:*:*:*:*:emea:*:*:*

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