CVE-2019-1597 | Cisco FXOS and NX-OS Lightweight Directory Access Protocol Denial of Service Vulnerabilities

Multiple vulnerabilities in the implementation of the Lightweight Directory Access Protocol (LDAP) feature in Cisco FXOS Software and Cisco NX-OS Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerabilities are due to the improper parsing of LDAP packets by an affected device. An attacker could exploit these vulnerabilities by sending an LDAP packet crafted using Basic Encoding Rules (BER) to an affected device. The LDAP packet must have a source IP address of an LDAP server configured on the targeted device. A successful exploit could cause the affected device to reload, resulting in a DoS condition. Firepower 4100 Series Next-Generation Firewalls are affected in versions prior to 2.0.1.201, 2.2.2.54, and 2.3.1.75. Firepower 9300 Security Appliances are affected in versions prior to 2.0.1.201, 2.2.2.54 and 2.3.1.75. MDS 9000 Series Multilayer Switches are affected in versions prior to 8.2(1). Nexus 3000 Series Switches are affected in versions prior to 7.0(3)I7(1). Nexus 3500 Platform Switches are affected in versions prior to 7.0(3)I7(2). Nexus 7000 and 7700 Series Switches are affected in versions prior to 8.2(1). Nexus 9000 Series Switches in Standalone NX-OS Mode are affected in versions prior to 7.0(3)I7(1). Cisco UCS 6200 and 6300 Fabric Interconnect devices are affected in versions prior to 3.2(2b).

Published: 2019-03-07 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2019-1597 is rated Moderate Risk (63.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.52%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2019-1597

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 2.35% 2.52% +0.17%
2 2025-11-21 0.89% 2.35% +1.46%
3 2025-11-18 0.89%

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-1597

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.6 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 4.0 [email protected]
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 3.6 [email protected]
7.8 2.0 HIGH
AV:N/AC:L/Au:N/C:N/I:N/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:C)
Complete availability impact.
10.0 6.9 [email protected]

Weakness enumeration for CVE-2019-1597

Affected software / configurations for CVE-2019-1597

Vendor Product Version Raw CPE
cisco firepower_extensible_operating_system > 2.2.2.54, < 2.3.1.75 cpe:2.3:o:cisco:firepower_extensible_operating_system:*:*:*:*:*:*:*:*
cisco nx-os < 8.2\(1\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os < 7.0\(3\)i7\(1\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os < 7.0\(3\)i7\(2\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os > 7.3\(2\)d1\(1\), < 8.2\(1\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco firepower_extensible_operating_system > 2.0.1.201, < 2.2.2.54 cpe:2.3:o:cisco:firepower_extensible_operating_system:*:*:*:*:*:*:*:*
cisco nx-os > 6.2\(20\), < 7.3\(2\)d1\(1\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco nx-os < 6.2\(20\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*
cisco firepower_extensible_operating_system < 2.0.1.201 cpe:2.3:o:cisco:firepower_extensible_operating_system:*:*:*:*:*:*:*:*
cisco nx-os < 3.2\(2b\) cpe:2.3:o:cisco:nx-os:*:*:*:*:*:*:*:*

References for CVE-2019-1597

cvelogic Threat Intelligence