CVE-2023-20173Network attack vector

Arbitrary file read via external entity expansion

Published May 18, 2023 · Updated Oct 25, 2024

XXE injection in Cisco Identity Services Engine allows remote authenticated users to read arbitrary operating-system files via XML upload. The web management interface parses uploaded XML files without properly restricting external entity references, causing the parser to resolve attacker-supplied file URIs against the underlying system. Valid Administrator credentials are required, and successful exploitation discloses local file contents without reported modification or service interruption.

CVSS severity4.9
Medium
EPSS probability0.77%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

XXE injection in Cisco Identity Services Engine allows remote authenticated users to read arbitrary operating-system files via XML upload. The web management interface parses uploaded XML files without properly restricting external entity references, causing the parser to resolve attacker-supplied file URIs against the underlying system. Valid Administrator credentials are required, and successful exploitation discloses local file contents without reported modification or service interruption.

The record

CVE
CVE-2023-20173
Published
May 18, 2023
Updated
Oct 25, 2024
Vendor
ClamAV
Product
Cisco Identity Services Engine
Classifications
CWE-611, T1005
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. May 18, 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 vectornetwork
Required privilegesadmin

What is affected?

ClamAV · Cisco Identity Services Engineversion=n/a

Published CVSS scores

4.9Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
4.9NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-611Improper Restriction of XML External Entity Reference
T1005Data from Local System

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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