CVE-2026-20320: Cisco BroadWorks flaw exploited in the wild, what we know

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.

• Severity: HIGH (CVSS 3.1 7.5, vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).
• Weakness: CWE-611.
• NVD published 2026-08-19, status Analyzed.

Anyone running Cisco BroadWorks in the version ranges below. Internet-facing instances are the priority.

• cisco broadworks application delivery platform: up to (not including) ri.2026.07.
• cisco broadworks application server: up to (not including) 2026.0.
• cisco broadworks profile server: up to (not including) 2026.07.
• cisco broadworks xtended services platform: up to (not including) 2026.07.

Version ranges come from the NVD CPE configuration. Confirm against the vendor advisory before you rely on them.

• Exploited in the wild: added to the CISA Known Exploited Vulnerabilities catalog on 2026-11-10; federal remediation due date 2026-11-24.

CISA added CVE-2026-20320 to its Known Exploited Vulnerabilities catalog on 2026-11-10. A KEV listing means CISA has evidence that attackers are using the flaw against real systems, not just that it could be used.

If your business runs Cisco BroadWorks, put this at the top of the patch list. CISA gave US federal agencies until 2026-11-24 to deal with it, and that is a sensible deadline for a small business too.

• Patch. Update to a fixed release: cisco broadworks application delivery platform ri.2026.07 or later; cisco broadworks application server 2026.0 or later; cisco broadworks profile server 2026.07 or later. These versions come from NVD's configuration data, so confirm them against the advisory from Cisco.
• If you cannot patch yet. Follow 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.
• Check your exposure. Find out whether Cisco BroadWorks can be reached from the internet, for example a VPN portal, an admin login page or a file-transfer site. Your firewall's port-forwarding rules and your IT provider's list of public-facing systems are the quickest places to look. Exposed copies come first.
• When to call IT support. Call your IT support provider now if you run Cisco BroadWorks and cannot confirm it is updated, if it was reachable from the internet before you patched it, or if you notice accounts, sign-ins or files you do not recognise. The last two can mean the system was already hit, and checking that properly takes someone who can read the logs.

• EPSS (probability of exploitation activity in the next 30 days): 0.39%, higher than 33% of all scored CVEs (as of 2026-11-10).
• CVERadar threat level: 53/100 (see methodology).
• Likely ATT&CK techniques: T1190 Exploit Public-Facing Application (inferred); T1005 Data from Local System (inferred).

1. Find every instance. List where Cisco BroadWorks runs, including test, DR and forgotten internet-facing systems, and record the installed version.

   show version

2. Upgrade to a fixed release. cisco broadworks application delivery platform: ri.2026.07 or later; cisco broadworks application server: 2026.0 or later; cisco broadworks profile server: 2026.07 or later; cisco broadworks xtended services platform: 2026.07 or later. Get the build from the vendor advisory.
3. If you can't patch today, follow 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.
4. Verify the fix. Re-run the version check above on every instance and confirm it reports the fixed build (ri.2026.07 or later). Re-scan from outside if the service is exposed.
5. Hunt for signs of earlier compromise. If the system was exposed before you patched, assume it may have been hit and check the items below.
6. Rotate credentials stored on or used by the affected system if you cannot rule out compromise, and keep the logs you reviewed.

Detection hints

• T1190 Exploit Public-Facing Application: Review WAF, reverse-proxy and application logs for unusual requests to BroadWorks (odd paths, oversized or encoded payloads, bursts of errors), going back to at least 2026-08-19.

Detection commands are generic starting points, not CVE-specific signatures. Use the indicators from the vendor advisory when it publishes them.

• NVD: CVE-2026-20320 nvd.nist.gov/vuln/detail/CVE-2026-20320
• CVE.org record www.cve.org/CVERecord?id=CVE-2026-20320
• Vendor link from CISA KEV sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/
• CISA KEV catalog www.cisa.gov/known-exploited-vulnerabilities-catalog
• FIRST EPSS (2026-11-10) api.first.org/data/v1/epss?cve=CVE-2026-20320