How severe is CVE-2018-15381?

CVE-2018-15381 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-2018-15381 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 87% (100th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-15381?

CVE-2018-15381 affects Cisco Unity Express. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-15381?

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-2018-15381 published?

CVE-2018-15381 was published on 2018-11-08 and last updated on 2026-06-17.

CVE-2018-15381

CVE-2018-15381 is a critical-severity vulnerability in Cisco Unity Express with a CVSS 3.x base score of 9.8. Its EPSS exploit-prediction score of 87% places it in the 100th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 10.0
EPSS exploit prediction: 87% (100th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Cisco Unity Express
Published: 2018-11-08
Last modified: 2026-06-17

Description

A Java deserialization vulnerability in Cisco Unity Express (CUE) could allow an unauthenticated, remote attacker to execute arbitrary shell commands with the privileges of the root user. The vulnerability is due to insecure deserialization of user-supplied content by the affected software. An attacker could exploit this vulnerability by sending a malicious serialized Java object to the listening Java Remote Method Invocation (RMI) service. A successful exploit could allow the attacker to execute arbitrary commands on the device with root privileges.

Frequently asked questions

What is CVE-2018-15381?: A Java deserialization vulnerability in Cisco Unity Express (CUE) could allow an unauthenticated, remote attacker to execute arbitrary shell commands with the privileges of the root user. The vulnerability is due to insecure deserialization of user-supplied content by the affected software. An attacker could exploit this vulnerability by sending a malicious serialized Java object to the listening Java Remote Method Invocation (RMI) service. A successful exploit could allow the attacker to execute arbitrary commands on the device with root privileges.
How severe is CVE-2018-15381?: CVE-2018-15381 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-2018-15381 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 87% (100th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-15381?: CVE-2018-15381 affects Cisco Unity Express. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-15381?: 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-2018-15381 published?: CVE-2018-15381 was published on 2018-11-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:cisco:unity_express:*:*:*:*:*:*:*:*

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