How severe is CVE-2018-0435?

CVE-2018-0435 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.

Is CVE-2018-0435 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-0435?

CVE-2018-0435 affects Cisco Umbrella. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-0435?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2018-0435 published?

CVE-2018-0435 was published on 2018-10-05 and last updated on 2026-06-17.

CVE-2018-0435

CVE-2018-0435 is a critical-severity vulnerability in Cisco Umbrella with a CVSS 3.x base score of 9.1. 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-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 6.5
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Cisco Umbrella
Published: 2018-10-05
Last modified: 2026-06-17

Description

A vulnerability in the Cisco Umbrella API could allow an authenticated, remote attacker to view and modify data across their organization and other organizations. The vulnerability is due to insufficient authentication configurations for the API interface of Cisco Umbrella. An attacker could exploit this vulnerability to view and potentially modify data for their organization or other organizations. A successful exploit could allow the attacker to read or modify data across multiple organizations.

Frequently asked questions

What is CVE-2018-0435?: A vulnerability in the Cisco Umbrella API could allow an authenticated, remote attacker to view and modify data across their organization and other organizations. The vulnerability is due to insufficient authentication configurations for the API interface of Cisco Umbrella. An attacker could exploit this vulnerability to view and potentially modify data for their organization or other organizations. A successful exploit could allow the attacker to read or modify data across multiple organizations.
How severe is CVE-2018-0435?: CVE-2018-0435 has a CVSS 3.x base score of 9.1, rated critical severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability high.
Is CVE-2018-0435 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-0435?: CVE-2018-0435 affects Cisco Umbrella. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-0435?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2018-0435 published?: CVE-2018-0435 was published on 2018-10-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:cisco:umbrella:*:*:*:*:*:*:*:*

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