Security readout for executives and security teams
Plain-English summary
This is a browser-based attack against Cisco Firepower Management Center’s web interface. If an FMC user is tricked into opening a crafted link, attacker-controlled script could run in that user’s browser session, potentially exposing sensitive browser-based information or affecting actions inside the interface.
Executive priority
Treat as a moderate-priority management-plane risk. Prioritize faster if FMC is broadly reachable, administrators use shared workstations, or the environment has elevated phishing risk.
Technical view
CVE-2020-3313 is a CWE-79 cross-site scripting issue in Cisco FMC Software’s web UI caused by insufficient validation of user-supplied input. Cisco describes an unauthenticated remote attacker scenario requiring user interaction through a crafted link. Successful exploitation could execute arbitrary script in the interface context or access sensitive browser-based information.
Likely exposure
Exposure is limited to organizations using Cisco Firepower Management Center Software. The source bundle does not provide affected version ranges, so teams must verify deployed FMC versions and whether the management web UI is reachable by administrators or other users.
Exploitation context
The bundle marks KEV as false and provides no cited evidence of active exploitation. Cisco’s description indicates social engineering is needed: the attacker persuades a web-interface user to open a crafted link.
Researcher notes
Public bundle details are limited: affected versions are listed as n/a. Note a source inconsistency: the CVSS vector says UI:N, while Cisco’s description says exploitation requires persuading a user to click a crafted link.
Mitigation direction
- Review Cisco’s advisory for affected and fixed FMC releases.
- Upgrade FMC Software if Cisco lists your deployed version as affected.
- Restrict FMC web UI access to trusted admin networks or VPN.
- Warn FMC administrators not to open untrusted FMC-related links.
- Monitor FMC web sessions for suspicious or unexpected activity.
Validation and detection
- Inventory all Cisco FMC deployments and software versions.
- Confirm whether the FMC web UI is internet-accessible or broadly reachable.
- Compare installed versions against Cisco’s advisory.
- Review administrative access logs for unusual browser sessions.
- Confirm compensating access controls around the management interface.
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-2020-3313 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
- 6.5 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/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:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N3.92.5Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
6.5MediumVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- 20200506 Cisco Firepower Management Center 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.