How severe is CVE-2018-15398?

CVE-2018-15398 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2018-15398 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-15398?

CVE-2018-15398 primarily affects Cisco Adaptive Security Appliance Software. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-15398?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-15398 published?

CVE-2018-15398 was published on 2018-10-05 and last updated on 2026-06-17.

CVE-2018-15398

CVE-2018-15398 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software with a CVSS 3.x base score of 4.0. 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-284.

Key facts

Severity: Medium (CVSS 3.x base score 4.0)
CVSS v2: 4.3
EPSS exploit prediction: 2% (77th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-284
Affected product: Cisco Adaptive Security Appliance Software
Published: 2018-10-05
Last modified: 2026-06-17

Description

A vulnerability in the per-user-override feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass an access control list (ACL) that is configured for an interface of an affected device. The vulnerability is due to errors that could occur when the affected software constructs and applies per-user-override rules. An attacker could exploit this vulnerability by connecting to a network through an affected device that has a vulnerable configuration. A successful exploit could allow the attacker to access resources that are behind the affected device and would typically be protected by the interface ACL.

Frequently asked questions

What is CVE-2018-15398?: A vulnerability in the per-user-override feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass an access control list (ACL) that is configured for an interface of an affected device. The vulnerability is due to errors that could occur when the affected software constructs and applies per-user-override rules. An attacker could exploit this vulnerability by connecting to a network through an affected device that has a vulnerable configuration. A successful exploit could allow the attacker to access resources that are behind the affected device and would typically be protected by the interface ACL.
How severe is CVE-2018-15398?: CVE-2018-15398 has a CVSS 3.x base score of 4.0, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2018-15398 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (77th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-15398?: CVE-2018-15398 primarily affects Cisco Adaptive Security Appliance Software. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-15398?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-15398 published?: CVE-2018-15398 was published on 2018-10-05 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:cisco:adaptive_security_appliance_software:9.6\(4.3\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:9.4\(2\):*:*:*:*:*:*:*
cpe:2.3:o:cisco:adaptive_security_appliance_software:9.4\(4\):*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.2.0:*:*:*:*:*:*:*

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