CVE-2023-20159Network attack vector

Unauthenticated root code execution via crafted request

Published May 18, 2023 · Updated Oct 28, 2024

Stack buffer overflow in Cisco Small Business Series Switches allows remote attackers to execute arbitrary code as root via the web interface. The web-based user interface fails to validate a crafted request before copying attacker-controlled data into a fixed-size stack buffer. No authentication or user interaction is required; successful exploitation gives root control of the switch and can interrupt network service.

CVSS severity9.8
Critical
EPSS probability10.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Stack buffer overflow in Cisco Small Business Series Switches allows remote attackers to execute arbitrary code as root via the web interface. The web-based user interface fails to validate a crafted request before copying attacker-controlled data into a fixed-size stack buffer. No authentication or user interaction is required; successful exploitation gives root control of the switch and can interrupt network service.

The record

CVE
CVE-2023-20159
Published
May 18, 2023
Updated
Oct 28, 2024
Vendor
ClamAV
Product
Cisco Business 350 Series Managed Switches
Classifications
CWE-120, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 18, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 28, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <3.3.0.16

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ClamAV · Cisco Business 350 Series Managed Switchesversion=0 <3.3.0.16
ClamAV · Cisco Business 250 Series Smart Switchesversion=0 <3.3.0.16
ClamAV · Cisco Small Business 300 Series Managed Switchesversion=0 <*
ClamAV · Cisco Small Business Smart and Managed Switchesversion=n/a
ClamAV · Cisco 550X Series Stackable Managed Switchesversion=0 <2.5.9.16
ClamAV · Cisco 250 Series Smart Switchesversion=0 <2.5.9.16
ClamAV · Cisco Small Business 200 Series Smart Switchesversion=0 <*
ClamAV · Cisco 350X Series Stackable Managed Switchesversion=0 <2.5.9.16
ClamAV · Cisco 350 Series Managed Switchesversion=0 <2.5.9.16
ClamAV · Cisco Small Business 500 Series Stackable Managed Switchesversion=0 <*

Published CVSS scores

9.8Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1190Exploit Public-Facing Application

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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo