Security readout for executives and security teams
Plain-English summary
CVE-2021-41025 affects Fortinet FortiWeb authentication in listed 6.0 through 6.4 releases. A remote unauthenticated attacker may bypass authentication and appear as a legitimate cluster peer, creating risk to confidentiality, integrity, and availability.
Executive priority
Treat as high priority for FortiWeb owners because it can bypass authentication remotely. Patch or apply Fortinet-approved remediation promptly, especially for internet-facing or broadly reachable appliances.
Technical view
The issue is in FortiWeb confd authentication and includes improper synchronization of a shared resource plus capture-replay authentication bypass. CVSS 3.1 is 7.3, network exploitable, low complexity, no privileges, no user interaction, unchanged scope, with low C/I/A impact.
Likely exposure
Exposure applies to Fortinet FortiWeb 6.4.1, 6.4.0, 6.3.0-6.3.15, 6.2.0-6.2.6, 6.1.0-6.1.2, and 6.0.0-6.0.7. Risk is higher where relevant FortiWeb services are reachable from untrusted networks.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. The CVSS vector indicates remote unauthenticated exploitation is possible, with exploit code maturity marked proof-of-concept in the supplied vector.
Researcher notes
Do not assume broader Fortinet product impact beyond FortiWeb versions named here. The bundle provides affected ranges and vulnerability class, but not detailed packet behavior, indicators, or fixed release details.
Mitigation direction
- Identify all FortiWeb appliances and record exact firmware versions.
- Prioritize affected versions for remediation under Fortinet advisory FG-IR-21-130.
- Check Fortinet guidance for fixed versions or vendor-approved workarounds.
- Restrict untrusted network access to FortiWeb management and clustering-related services.
- Monitor FortiWeb logs for unexpected cluster peer authentication activity.
Validation and detection
- Compare FortiWeb versions against the affected ranges in the CVE record.
- Confirm whether appliances run FortiWeb 6.0.x, 6.1.x, 6.2.x, 6.3.x, or 6.4.x listed as affected.
- Review network exposure for FortiWeb services reachable from external or untrusted segments.
- Check change records for Fortinet advisory FG-IR-21-130 remediation.
- Validate monitoring covers authentication and cluster peer events.
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.
Credential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-41025 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
- High
- CVSS
- 7.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C
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:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C3.93.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.3HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L/E:P/RL:U/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://fortiguard.com/advisory/FG-IR-21-130CVE reference · x_refsource_CONFIRM
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.