# CVE-2026-20320: Cisco BroadWorks Improper Restriction of XML External Entity Reference Vulnerability

Status: published. Published: 2026-08-19. Updated: 2026-11-13.

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.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Cisco / Cisco BroadWorks: Version not specified (affected). Source: CNA: cisco

## NVD configuration conditions

Affected CPE matches depend on the following AND/OR and negation conditions:

```json
[
  {
    "negate": false,
    "nodes": [
      {
        "cpeMatch": [
          {
            "criteria": "cpe:2.3:a:cisco:broadworks_application_delivery_platform:*:*:*:*:*:*:*:*",
            "versionEndExcluding": "ri.2026.07",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:cisco:broadworks_application_server:*:*:*:*:release_independent:*:*:*",
            "versionEndExcluding": "2026.0",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:cisco:broadworks_profile_server:*:*:*:*:release_independent:*:*:*",
            "versionEndExcluding": "2026.07",
            "vulnerable": true
          },
          {
            "criteria": "cpe:2.3:a:cisco:broadworks_xtended_services_platform:*:*:*:*:release_independent:*:*:*",
            "versionEndExcluding": "2026.07",
            "vulnerable": true
          }
        ],
        "negate": false,
        "operator": "OR"
      }
    ],
    "operator": "OR"
  }
]
```

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N; source: CNA: cisco

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N; source: NVD: psirt@cisco.com

- CISA KEV: listed; 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.; due 2026-11-24

- EPSS: 0.98% as of 2026-11-13; percentile 62.63%

- SSVC: exploitation active; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-611

## Exploit evidence

- exploit: https://malbearlabs.com/posts/operation-snowball-inside-an-autonomous-ai-intrusion-campaign (134c704f-9b21-4f2e-91b3-4a467353bcc0)

## References

- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-bworks-xxe-uwUd7CEt (CNA: cisco)

- https://malbearlabs.com/posts/operation-snowball-inside-an-autonomous-ai-intrusion-campaign (ADP: CISA-ADP; third-party-advisory)

- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20320 (ADP: CISA-ADP; government-resource)

- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-bworks-xxe-uwUd7CEt (psirt@cisco.com; Vendor Advisory)

- https://malbearlabs.com/posts/operation-snowball-inside-an-autonomous-ai-intrusion-campaign (134c704f-9b21-4f2e-91b3-4a467353bcc0; Exploit, Third Party Advisory)

- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20320 (134c704f-9b21-4f2e-91b3-4a467353bcc0; US Government Resource)

## Provenance

- CNA: cisco: https://www.cve.org/CVERecord?id=CVE-2026-20320; retrieved 2026-11-13; source updated 2026-11-13

- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-20320; retrieved 2026-11-11; source updated 2026-11-11

- CISA KEV: https://www.cisa.gov/known-exploited-vulnerabilities-catalog; retrieved 2026-11-11; source updated Not reported

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2026-20320; retrieved 2026-11-13; source updated Not reported

Revision: 76192415759ab46aace6ea0140e9ec787386bd6104a5ab6a02ccd49f63eaf313

Canonical: https://y2.dev/cve/CVE-2026-20320

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