How severe is CVE-2018-6535?

CVE-2018-6535 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-6535 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6535?

CVE-2018-6535 affects Icinga. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-6535?

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-2018-6535 published?

CVE-2018-6535 was published on 2018-02-27 and last updated on 2026-06-17.

CVE-2018-6535

CVE-2018-6535 is a high-severity vulnerability in Icinga with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 4.3
EPSS exploit prediction: 1% (68th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Icinga
Published: 2018-02-27
Last modified: 2026-06-17

Description

An issue was discovered in Icinga 2.x through 2.8.1. The lack of a constant-time password comparison function can disclose the password to an attacker.

Frequently asked questions

What is CVE-2018-6535?: An issue was discovered in Icinga 2.x through 2.8.1. The lack of a constant-time password comparison function can disclose the password to an attacker.
How severe is CVE-2018-6535?: CVE-2018-6535 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-6535 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (68th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6535?: CVE-2018-6535 affects Icinga. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-6535?: 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-2018-6535 published?: CVE-2018-6535 was published on 2018-02-27 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:icinga:icinga:*:*:*:*:*:*:*:*

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