CVE-2023-20089

Device reload via LLDP parser memory leak

Published Feb 23, 2023 · Updated Oct 25, 2024

Denial of service in Cisco NX-OS System Software in ACI Mode allows attackers to reload Nexus 9000 devices via crafted LLDP packets. Incorrect error checking while parsing ingress LLDP packets lets a steady stream of crafted packets leak LLDP-process memory until the device exhausts memory and reloads. Packets must target a directly connected LLDP-enabled interface from the same Layer 2 broadcast domain; transit traffic cannot reach the flaw.

CVSS severity7.4
High
EPSS probability0.30%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Cisco NX-OS System Software in ACI Mode allows attackers to reload Nexus 9000 devices via crafted LLDP packets. Incorrect error checking while parsing ingress LLDP packets lets a steady stream of crafted packets leak LLDP-process memory until the device exhausts memory and reloads. Packets must target a directly connected LLDP-enabled interface from the same Layer 2 broadcast domain; transit traffic cannot reach the flaw.

The record

CVE
CVE-2023-20089
Published
Feb 23, 2023
Updated
Oct 25, 2024
Vendor
ClamAV
Product
Cisco NX-OS System Software in ACI Mode
Classifications
CWE-789, CWE-401, T1498
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 23, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 25, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=n/a

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco NX-OS System Software in ACI Modeversion=n/a

Published CVSS scores

7.4Cisco Systems, Inc.CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:X/RL:X/RC:X

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-789Memory Allocation with Excessive Size Value
CWE-401Missing Release of Memory after Effective Lifetime
T1498Network Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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