How severe is CVE-2018-6328?

CVE-2018-6328 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-6328 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 66% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6328?

CVE-2018-6328 affects Kaseya Unitrends Backup. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-6328?

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-2018-6328 published?

CVE-2018-6328 was published on 2018-03-14 and last updated on 2026-06-17.

CVE-2018-6328

CVE-2018-6328 is a critical-severity vulnerability in Kaseya Unitrends Backup with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 66% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-287.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 66% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Kaseya Unitrends Backup
Published: 2018-03-14
Last modified: 2026-06-17

Description

It was discovered that the Unitrends Backup (UB) before 10.1.0 user interface was exposed to an authentication bypass, which then could allow an unauthenticated user to inject arbitrary commands into its /api/hosts parameters using backquotes.

Frequently asked questions

What is CVE-2018-6328?: It was discovered that the Unitrends Backup (UB) before 10.1.0 user interface was exposed to an authentication bypass, which then could allow an unauthenticated user to inject arbitrary commands into its /api/hosts parameters using backquotes.
How severe is CVE-2018-6328?: CVE-2018-6328 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-6328 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 66% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6328?: CVE-2018-6328 affects Kaseya Unitrends Backup. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-6328?: 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-2018-6328 published?: CVE-2018-6328 was published on 2018-03-14 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:kaseya:unitrends_backup:*:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

CVE-2026-45480 — Critical (CVSS 10.0): Improper authentication in Azure Active Directory allows an unauthorized attacker to elevate privileges over a network.
CVE-2026-46389 — Critical (CVSS 10.0): UDS Identity Config builds the Keycloak configuration image (realm, plugins, theme, truststore, JARs) consumed by UDS…
CVE-2026-10611 — Critical (CVSS 10.0): An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement.…
CVE-2026-47280 — Critical (CVSS 10.0): Improper authentication in Azure Resource Manager (ARM) allows an unauthorized attacker to elevate privileges over a…
CVE-2026-42822 — Critical (CVSS 10.0): Improper authentication in Azure Local Disconnected Operations allows an unauthorized attacker to elevate privileges…
CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

Browse all CWE-287 (Improper Authentication) vulnerabilities →