Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2023-27997

FortiOS-6K7K

Fortinet / FortiOS-6K7K · 7.0.10

Watch CVE-2023-27997 Browse KEV feed
Severity
CVSS 9.2 · Critical
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
85.7%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2023-27997 is an unauthenticated vulnerability affecting Fortinet FortiOS-6K7K and 2 other products. A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and...

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Fortinet / FortiOS-6K7K 7.0.10.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

FortiOS-6K7K

A heap-based buffer overflow vulnerability [CWE-122] in FortiOS version 7.2.4 and below, version 7.0.11 and below, version 6.4.12 and below, version 6.0.16 and below and FortiProxy version 7.2.3 and below, version 7.0.9 and below, version 2.0.12 and below, version 1.2 all versions, version 1.1 all versions SSL-VPN may allow a remote attacker to execute arbitrary code or commands via specifically crafted requests.

Fortinet Affected
FortiOS-6K7K
7.0.10 7.0.5 6.4.12 6.4.10 6.4.8 6.4.6 6.4.2 Through 6.2.13 Through 6.2.7 6.2.4 Through 6.0.16 6.0.10
Fortinet Affected
FortiProxy
Through 7.2.3 Through 7.0.9 Through 2.0.12 Through 1.2.13 Through 1.1.6
Fortinet Affected
FortiOS
Through 7.2.4 Through 7.0.11 Through 6.4.12 Through 6.2.13 Through 6.0.16
Published
13 Jun 2023
Exploitation Reported
13 Jun 2023
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

edge cisa malware ransomware nessus_scanner ios

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 13 Jun 2023

A trusted third party reported exploitation.

Used in malware

CISA

Recorded 13 Jun 2023

Malware families have been linked to exploitation of this CVE.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

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Source Added
CISA First 2023-06-13 00:00 UTC
CVE 2026-07-31 04:10 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nessus https://www.tenable.com/plugins/nessus/177116 02 Jun 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.2 Critical

Potential damage if exploited. Separate from whether attackers are using it.

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

EPSS

85.7%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Heap-based Buffer Overflow CWE-122

Recent mention · Tenable Blog

CVE-2025-32756: Zero-Day Vulnerability in Multiple Fortinet Products Exploited in the Wild

Fortinet has observed threat actors exploiting CVE-2025-32756, a critical zero-day arbitrary code execution vulnerability which affects multiple Fortinet products including FortiVoice, FortiMail, FortiNDR, FortiRecorder and FortiCamera.BackgroundOn May 13th, Fortinet published...

Read full advisory

Timeline

From disclosure to observed exploitation

  1. 04:10 UTC

    KEV confirmed by CVE

    Exploitation attested by an external source

  2. 09:26 UTC

    Nessus plugin available

    Scanner coverage available

  3. 08:41 UTC

    CVE published

    Vulnerability disclosed publicly

  4. 00:00 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  5. 00:00 UTC

    First public exploitation report

    Exploit observed in malware

  6. 10:09 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

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  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2023-27997

Free JSON includes basic KEV fields 
{
  "cve_id": "CVE-2023-27997",
  "confidence": "Confirmed",
  "cvss_score": 9.2,
  "cvss_estimated": false,
  "epss_score": 0.85689,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}