A vulnerability, which was classified as problematic, has been found in Fortinet FortiOS up to 6.2.1 (Firewall Software). This issue affects an unknown function of the component ECDSA Handler. The manipulation with an unknown input leads to a entropy vulnerability (PRNG). Using CWE to declare the problem leads to CWE-331. The product uses an algorithm or scheme that produces insufficient entropy, leaving patterns or clusters of values that are more likely to occur than others. Impacted is confidentiality. The summary by CVE is:

An Insufficient Entropy in PRNG vulnerability in Fortinet FortiOS 6.2.1 and below for device not enable hardware TRNG token and models not support builtin TRNG seed allows attacker to theoretically recover the long term ECDSA secret in a TLS client with a RSA handshake and mutual ECDSA authentication via the help of flush+reload side channel attacks in FortiGate VM models only.

The weakness was disclosed 10/24/2019 as FG-IR-19-186 (Website). The advisory is shared at fortiguard.com. The identification of this vulnerability is CVE-2019-15703 since 08/27/2019. The exploitation is known to be difficult. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1600.001 for this issue.

Upgrading eliminates this vulnerability.

Productinfo

Type

• Firewall Software

Vendor

• Fortinet

Name

• FortiOS

Version

• 6.2.0
• 6.2.1

License

• commercial

CPE 2.3info

• 🔍
• 🔍

CPE 2.2info

• 🔍
• 🔍

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Discussion