How severe is CVE-2020-15336?

CVE-2020-15336 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 none, integrity high, and availability none.

Is CVE-2020-15336 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-15336?

CVE-2020-15336 primarily affects Zyxel Cloudcnm Secumanager. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-15336?

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-2020-15336 published?

CVE-2020-15336 was published on 2020-06-26 and last updated on 2026-06-17.

CVE-2020-15336

CVE-2020-15336 is a high-severity vulnerability in Zyxel Cloudcnm Secumanager 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-306.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (56th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Zyxel Cloudcnm Secumanager
Published: 2020-06-26
Last modified: 2026-06-17

Description

Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has no authentication for /cnr requests.

Frequently asked questions

What is CVE-2020-15336?: Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has no authentication for /cnr requests.
How severe is CVE-2020-15336?: CVE-2020-15336 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 none, integrity high, and availability none.
Is CVE-2020-15336 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (56th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-15336?: CVE-2020-15336 primarily affects Zyxel Cloudcnm Secumanager. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-15336?: 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-2020-15336 published?: CVE-2020-15336 was published on 2020-06-26 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:zyxel:cloudcnm_secumanager:3.1.0:*:*:*:*:*:*:*
cpe:2.3:a:zyxel:cloudcnm_secumanager:3.1.1:*:*:*:*:*:*:*

More vulnerabilities in Zyxel Cloudcnm Secumanager

CVE-2020-15347 — Critical (CVSS 9.8): Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has the q6xV4aW8bQ4cfD-b password for the axiros account.
CVE-2020-15332 — Critical (CVSS 9.8): Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has weak /opt/axess/etc/default/axess permissions.
CVE-2020-15331 — Critical (CVSS 9.8): Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has a hardcoded OAUTH_SECRET_KEY in /opt/axess/etc/default/axess.
CVE-2020-15323 — Critical (CVSS 9.8): Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has the cloud1234 password for the a1@chopin account default credentials.
CVE-2020-15322 — Critical (CVSS 9.8): Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has the wbboEZ4BN3ssxAfM hardcoded password for the debian-sys-maint account.
CVE-2020-15321 — Critical (CVSS 9.8): Zyxel CloudCNM SecuManager 3.1.0 and 3.1.1 has the axzyxel password for the livedbuser account.

All CVEs affecting Zyxel Cloudcnm Secumanager →

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