CyberSecBulletin
CVE-2026-20320Exploited in the wildNVD status: Modified

Cisco BroadWorks Improper Restriction of XML External Entity Reference

Published Updated By the CyberSecBulletin desk

CVE-2026-20320 is a high-severity improper restriction of XML external entity reference vulnerability in Cisco BroadWorks from Cisco, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. CISA added it to the Known Exploited Vulnerabilities catalogue on November 10, 2026, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Broadworks Application Delivery Platform to ri.2026.07 or a later version.
  2. Update Broadworks Application Server to 2026.0 or a later version.
  3. Update Broadworks Profile Server to 2026.07 or a later version.
  4. CISA's required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
  5. Read the advisory on sec.cloudapps.cisco.com for workarounds and exact fixed builds.
  6. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
CiscoCisco BroadWorksNot specified in the recordNot stated
CiscoBroadworks Application Delivery Platformbefore ri.2026.07ri.2026.07
CiscoBroadworks Application Serverbefore 2026.02026.0
CiscoBroadworks Profile Serverbefore 2026.072026.07
CiscoBroadworks Xtended Services Platformbefore 2026.072026.07

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by CNA (cisco.com).

Official description

A vulnerability in the Open Client Interface (OCI) XML Parser of Cisco BroadWorks could allow an unauthenticated, remote attacker to read sensitive configuration information on an affected system. This vulnerability exists because XML entries are improperly parsed due to external entity resolution being allowed by default. An attacker could exploit this vulnerability by sending a crafted XML message to the Open Client Interface – Provisioning (OCI-P) service. A successful exploit could allow the attacker to view sensitive files from the filesystem with the privileges of the Cisco BroadWorks user.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Restriction of XML External Entity Reference

The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output.

How developers prevent this class of flaw

  • Many XML parsers and validators can be configured to disable external entity expansion.

More Improper Restriction of XML External Entity Reference vulnerabilities (CWE-611)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: partial).
  3. Added to CISA's Known Exploited Vulnerabilities catalogue.
  4. Record last changed materially (score, affected products, status or references).
  5. Deadline for US federal agencies to remediate, set by CISA.

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Our coverage

Other vulnerabilities in Cisco BroadWorks

All Cisco BroadWorks vulnerabilities

Recent Improper Restriction of XML External Entity Reference vulnerabilities

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