CVE-2023-33306Network attack vector

SSL-VPN service interruption via crafted bookmark

Published Jun 16, 2023 · Updated Oct 22, 2024

NULL pointer dereference in Fortinet FortiOS and FortiProxy SSL-VPN allows remote authenticated users to interrupt the SSL-VPN service. The SSL-VPN request handler dereferences a null pointer while processing a specifically crafted bookmark parameter. A valid SSL-VPN session is required, and a successful request interrupts SSL-VPN availability without affecting confidentiality or integrity.

CVSS severity6.5
Medium
EPSS probability0.84%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in Fortinet FortiOS and FortiProxy SSL-VPN allows remote authenticated users to interrupt the SSL-VPN service. The SSL-VPN request handler dereferences a null pointer while processing a specifically crafted bookmark parameter. A valid SSL-VPN session is required, and a successful request interrupts SSL-VPN availability without affecting confidentiality or integrity.

The record

CVE
CVE-2023-33306
Published
Jun 16, 2023
Updated
Oct 22, 2024
Vendor
Fortinet
Product
FortiOS
Classifications
CWE-476, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 16, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 22, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=6.4.0 <=6.4.12
  2. Affected versionversion=7.0.0 <=7.0.10
  3. Affected versionversion=7.2.0 <=7.2.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fortinet · FortiOSversion=6.4.0 <=6.4.12; version=7.0.0 <=7.0.10; version=7.2.0 <=7.2.4
Fortinet · FortiProxyversion=7.0.0 <=7.0.9; version=7.2.0 <=7.2.3

Published CVSS scores

6.5Fortinet, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-476NULL Pointer Dereference
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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