CVE-2021-1530Network attack vector

File disclosure and service interruption via XXE parsing

Published May 6, 2021 · Updated Nov 8, 2024

XXE injection in Cisco BroadWorks Messaging Server 22.0 allows remote authenticated users to read local files or interrupt service. The web management interface parses uploaded XML without restricting external entity resolution, letting entity references retrieve files or consume server resources. A valid account and crafted XML upload are required; exploitation discloses sensitive files or causes a partial service interruption.

CVSS severity5.4
Medium
EPSS probability1.11%
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 BroadWorks Messaging Server 22.0 allows remote authenticated users to read local files or interrupt service. The web management interface parses uploaded XML without restricting external entity resolution, letting entity references retrieve files or consume server resources. A valid account and crafted XML upload are required; exploitation discloses sensitive files or causes a partial service interruption.

The record

CVE
CVE-2021-1530
Published
May 6, 2021
Updated
Nov 8, 2024
Vendor
ClamAV
Product
Cisco BroadWorks
Classifications
CWE-611, T1499.004, T1005
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 6, 2021CVE publishedPublication date reported by the CVE source.
  2. Nov 8, 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 privilegesauthenticated

What is affected?

ClamAV · Cisco BroadWorksversion=n/a

Published CVSS scores

5.5NISTAV:N/AC:L/Au:S/C:P/I:N/A:P
5.4Cisco Systems, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L/E:X/RL:X/RC:X
7.1NISTCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:L

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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-611Improper Restriction of XML External Entity Reference
T1499.004Application or System Exploitation
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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