Security readout for executives and security teams
Plain-English summary
CVE-2021-1477 is an access-control weakness in Cisco Firepower Management Center. An authenticated remote user could reach internal services they should not access, potentially overwriting policies and changing device operation. It is rated medium, but the business impact can matter because FMC controls security policy.
Executive priority
Treat as a moderate-priority control-plane issue. It is not reported as actively exploited, but FMC policy integrity affects security operations, so validate exposure and follow Cisco guidance during the next security maintenance cycle.
Technical view
The flaw is CWE-284 in Cisco FMC Software. Insufficient access-control enforcement allows a low-privileged authenticated network attacker to directly access internal services. The CVSS 3.1 score is 4.3, with low attack complexity, low privileges required, no user interaction, and low integrity impact.
Likely exposure
Exposure is limited to organizations running affected Cisco Firepower Management Center Software where an attacker has authenticated access. The source bundle does not identify specific affected versions, fixed versions, or deployment conditions.
Exploitation context
CISA KEV is false in the provided bundle, and no cited source states active exploitation. The credible scenario is misuse of valid credentials or compromised low-privileged access to reach unauthorized FMC internal services.
Researcher notes
The bundle lacks affected version ranges and fixed-release details. Analysis should avoid claiming broader Cisco product impact. Focus validation on authenticated authorization boundaries, policy integrity, and whether the specific FMC build is listed by Cisco.
Mitigation direction
- Review Cisco’s advisory for affected releases and official remediation guidance.
- Upgrade or apply vendor-provided fixes if Cisco identifies them for your FMC version.
- Restrict FMC access to trusted administrators and management networks.
- Review FMC accounts and remove unnecessary low-privileged access.
- Monitor FMC policy changes for unauthorized or unexpected modifications.
Validation and detection
- Inventory Cisco FMC deployments and record software versions.
- Compare versions against Cisco’s advisory and CVE record.
- Review FMC user roles for least-privilege enforcement.
- Check change history for unexpected access-control or policy overwrites.
- Confirm management access is limited to approved networks and users.
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-284: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. 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-2021-1477 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
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/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:L/UI:N/S:U/C:N/I:L/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- 20210428 Cisco Firepower Management Center Software Policy 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 Access Control
Improper Access Control represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.