How severe is CVE-2020-3135?

CVE-2020-3135 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-3135 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3135?

CVE-2020-3135 affects Cisco Unified Communications Manager. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3135?

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-2020-3135 published?

CVE-2020-3135 was published on 2020-09-23 and last updated on 2026-06-17.

CVE-2020-3135

CVE-2020-3135 is a high-severity vulnerability in Cisco Unified Communications Manager with a CVSS 3.x base score of 8.8. 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-352.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.8
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-352
Affected product: Cisco Unified Communications Manager
Published: 2020-09-23
Last modified: 2026-06-17

Description

A vulnerability in the web-based management interface of Cisco Unified Communications Manager (UCM) could allow an unauthenticated, remote attacker to conduct a cross-site request forgery (CSRF) attack on an affected device. The vulnerability is due to insufficient CSRF protections for the web-based management interface on an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to follow a malicious link. A successful exploit could allow the attacker to perform arbitrary actions with the privilege level of the targeted user.

Frequently asked questions

What is CVE-2020-3135?: A vulnerability in the web-based management interface of Cisco Unified Communications Manager (UCM) could allow an unauthenticated, remote attacker to conduct a cross-site request forgery (CSRF) attack on an affected device. The vulnerability is due to insufficient CSRF protections for the web-based management interface on an affected device. An attacker could exploit this vulnerability by persuading a user of the interface to follow a malicious link. A successful exploit could allow the attacker to perform arbitrary actions with the privilege level of the targeted user.
How severe is CVE-2020-3135?: CVE-2020-3135 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-3135 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3135?: CVE-2020-3135 affects Cisco Unified Communications Manager. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3135?: 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-2020-3135 published?: CVE-2020-3135 was published on 2020-09-23 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ucm-csrf-NbhZTxL

Affected products (1)

cpe:2.3:a:cisco:unified_communications_manager:*:*:*:*:*:*:*:*

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