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CVE Record

CVE-2021-36179: A stack-based buffer overflow in Fortinet FortiWeb version 6.3.14 and below, 6.2.4 and below allows attacke...

A stack-based buffer overflow in Fortinet FortiWeb version 6.3.14 and below, 6.2.4 and below allows attacker to execute unauthorized code or commands via crafted parameters in CLI command execution

HighCVSS 8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

Fortinet FortiWeb versions 6.3.14 and below and 6.2.4 and below contain a stack-based buffer overflow. A lower-privileged attacker on an adjacent network could use crafted CLI command parameters to run unauthorized code or commands, potentially compromising the appliance.

Executive priority

Treat this as high priority for FortiWeb environments. The issue affects a security appliance and could allow code or command execution after low-privilege adjacent access. Confirm exposure quickly and follow Fortinet guidance.

Technical view

The CVE describes stack-based buffer overflow in FortiWeb CLI command execution parameter handling. CVSS 3.1 is 8.0 with adjacent-network access, low complexity, low privileges, no user interaction, and high confidentiality, integrity, and availability impact.

Likely exposure

Organizations running Fortinet FortiWeb 6.3.0 through 6.3.14 or 6.2.0 through 6.2.4 are potentially exposed, especially where administrative or CLI access is reachable from adjacent networks or insufficiently restricted.

Exploitation context

The provided sources do not establish active exploitation, and KEV is false. The CVSS vector includes E:F, indicating functional exploit maturity in the scoring data, but the bundle does not provide exploit details.

Researcher notes

Evidence is limited to CVE metadata and Fortinet advisory reference. Do not assume internet-routable exploitation from AV:A. Focus validation on version inventory, management-plane reachability, privilege boundaries, and vendor advisory status.

Mitigation direction

  • Identify all FortiWeb appliances and record firmware versions.
  • Prioritize FortiWeb 6.3.14 and below or 6.2.4 and below.
  • Check Fortinet advisory FG-IR-20-206 for vendor-approved fixed releases or mitigations.
  • Restrict administrative and CLI access to trusted management networks.
  • Review appliance access controls and privileged account exposure.

Validation and detection

  • Compare deployed FortiWeb versions against the affected version ranges.
  • Confirm management interfaces are not reachable from untrusted adjacent networks.
  • Review administrative logs for unusual CLI activity or unexpected command execution.
  • Verify remediation status against Fortinet advisory FG-IR-20-206.
  • Document any compensating controls pending vendor-guided upgrade.
Prepared
Confidence
medium
Sources
3

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

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.

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CVE-2021-36179 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
8 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:X/RC:X

Official CVE source material

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.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We 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.

ScoreVersionSeverityVectorExploitImpactSource
8CVSS 3.1HighCVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:X/RC:X2.15.9Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

8High
CVSS 3.1 vector shape for CVE-2021-36179Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:F/RL:X/RC:X

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
FortinetFortinet FortiWebFortiWeb 6.3.14, 6.3.13, 6.3.12, 6.3.11, 6.3.10, 6.3.9, 6.3.8, 6.3.7, 6.3.6, 6.3.5, 6.3.4, 6.3.3, 6.3.2, 6.3.1, 6.3.0, 6.2.4, 6.2.3, 6.2.2, 6.2.1, 6.2.0Listed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.