Security readout for executives and security teams
Plain-English summary
Cisco Unified CM and Unified CM SME had a web interface flaw that could let an attacker run script in a user's browser after convincing that user to open a crafted link. This is not a server takeover by itself, but it can expose browser-accessible data or alter what the user sees in that interface.
Executive priority
Treat this as a moderate-priority communications platform issue. It needs normal patch governance and exposure reduction, especially if the web UI is broadly reachable or used by privileged administrators. Escalate if Cisco guidance shows your deployed release is affected and no access controls limit UI reachability.
Technical view
CVE-2020-3346 is a CWE-79 cross-site scripting issue in the Cisco Unified CM web UI caused by insufficient validation of user-supplied input. CVSS 3.1 is 6.1: network reachable, low complexity, no privileges required, user interaction required, changed scope, low confidentiality and integrity impact, no availability impact.
Likely exposure
Exposure is most likely where Cisco Unified Communications Manager or Unified CM SME web interfaces are reachable by users. The source bundle does not identify affected release numbers, CPEs, or deployment conditions, so teams must compare their installed versions with Cisco's advisory.
Exploitation context
The bundle does not show CISA KEV listing or active exploitation evidence. Exploitation requires social engineering: an attacker must persuade a user of the affected interface to open a crafted link. Successful exploitation could run script in the interface context or access sensitive browser-based information.
Researcher notes
The CVSS vector is consistent with reflected or link-triggered XSS: AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N. The bundle names Cisco Unified CM and Unified CM SME but does not provide affected versions or fix details. Avoid assuming exploitation in the wild without KEV or corroborating source evidence.
Mitigation direction
- Review Cisco advisory cisco-sa-cucm-selfcare-drASc7sr for affected and fixed releases.
- Apply Cisco-recommended fixed software or mitigations where applicable.
- Restrict Unified CM web UI access to trusted networks or VPN paths.
- Limit administrative and self-care interface access to required users only.
- Warn users with access to avoid unsolicited Unified CM links.
Validation and detection
- Inventory Cisco Unified CM and Unified CM SME deployments.
- Confirm installed releases against Cisco's advisory.
- Review whether the web UI is internet-accessible or broadly reachable internally.
- Check logs and user reports for suspicious link-driven sessions.
- Verify compensating access controls around Unified CM interfaces.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2020-3346 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- 20200805 Cisco Unified Communications Manager Cross-Site Scripting VulnerabilityCVE reference · vendor-advisory, x_refsource_CISCO
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.