Fortinet FortiWeb up to 7.0.10/7.2.10/7.4.7 HTTPS Request syntactically invalid structure

CVSS Meta Temp Score
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CTI Interest Score
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6.9$0-$5k0.00

Summaryinfo

A vulnerability has been found in Fortinet FortiWeb up to 7.0.10/7.2.10/7.4.7 and classified as problematic. The impacted element is an unknown function of the component HTTPS Request Handler. Performing a manipulation results in improper handling of syntactically invalid structure. This vulnerability is known as CVE-2023-42784. Remote exploitation of the attack is possible. No exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability classified as problematic has been found in Fortinet FortiWeb up to 7.0.10/7.2.10/7.4.7. This affects an unknown part of the component HTTPS Request Handler. The manipulation with an unknown input leads to a improper handling of syntactically invalid structure vulnerability. CWE is classifying the issue as CWE-228. The product does not handle or incorrectly handles input that is not syntactically well-formed with respect to the associated specification. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

An improper handling of syntactically invalid structure in Fortinet FortiWeb at least verions 7.4.0 through 7.4.6 and 7.2.0 through 7.2.10 and 7.0.0 through 7.0.10 allows attacker to execute unauthorized code or commands via HTTP/S crafted requests.

The weakness was published by Nikola Kojic with RAS-IT as FG-IR-23-115. It is possible to read the advisory at fortiguard.fortinet.com. This vulnerability is uniquely identified as CVE-2023-42784 since 09/14/2023. The exploitability is told to be difficult. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 232624 (Fortinet FortiWeb Web application firewall rules bypass by using an empty filename (FG-IR-23-115)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (232624). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.9

VulDB Base Score: 5.6
VulDB Temp Score: 5.4
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CNA Base Score: 5.6
CNA Vector (fortinet): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Improper handling of syntactically invalid structure
CWE: CWE-228 / CWE-20
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 232624
Nessus Name: Fortinet FortiWeb Web application firewall rules bypass by using an empty filename (FG-IR-23-115)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

09/14/2023 🔍
03/11/2025 +544 days 🔍
03/11/2025 +0 days 🔍
07/23/2025 +133 days 🔍

Sourcesinfo

Vendor: fortinet.com

Advisory: FG-IR-23-115
Researcher: Nikola Kojic
Organization: RAS-IT
Status: Confirmed

CVE: CVE-2023-42784 (🔍)
GCVE (CVE): GCVE-0-2023-42784
GCVE (VulDB): GCVE-100-299295

Entryinfo

Created: 03/11/2025 16:25
Updated: 07/23/2025 00:31
Changes: 03/11/2025 16:25 (64), 03/12/2025 07:33 (2), 03/27/2025 09:49 (2), 03/27/2025 09:50 (1), 07/23/2025 00:31 (12)
Complete: 🔍
Committer: nikolak
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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