Fortinet FortiOS up to 7.6.6 LDAP Credential default key ⚔ [Disputed]

Summaryinfo

A vulnerability was found in Fortinet FortiOS up to 7.6.6. It has been classified as problematic. This issue affects some unknown processing of the component LDAP Credential Handler. Performing a manipulation results in default key. This vulnerability is identified as CVE-2026-25815. The attack is only possible with local access. There is not any exploit available. There is ongoing doubt regarding the real existence of this vulnerability.

Detailsinfo

A vulnerability classified as problematic has been found in Fortinet FortiOS up to 7.6.6. This affects an unknown code block of the component LDAP Credential Handler. The manipulation with an unknown input leads to a default key vulnerability. CWE is classifying the issue as CWE-1394. The product uses a default cryptographic key for potentially critical functionality. This is going to have an impact on confidentiality. The summary by CVE is:

Fortinet FortiOS through 7.6.6 allows attackers to decrypt LDAP credentials stored in device configuration files, as exploited in the wild from 2025-12-16 through 2026 (by default, the encryption key is the same across all customers' installations). NOTE: the Supplier's position is that the instance of CWE-1394 is not a vulnerability because customers "are supposed to enable" a non-default option that eliminates the weakness. However, that non-default option can disrupt functionality as shown in the "Managing FortiGates with private data encryption" document, and is therefore intentionally not a default option.

The advisory is shared at cert.at. This vulnerability is uniquely identified as CVE-2026-25815 since 02/05/2026. The exploitability is told to be difficult. An attack has to be approached locally. Neither technical details nor an exploit are publicly available.

The real existence of this vulnerability is still doubted at the moment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-5525). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Firewall Software

Vendor

• Fortinet

Name

• FortiOS

Version

• 7.6.0
• 7.6.1
• 7.6.2
• 7.6.3
• 7.6.4
• 7.6.5
• 7.6.6

License

• commercial

Website

• Vendor: https://www.fortinet.com/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion