CVE-2019-1715
MediumCVSS 5.3Exploitation Probability (EPSS)
High risk75th percentile - higher than 75% of all known CVEs
Summary
A vulnerability in the DRBG (PRNG) used in Cisco ASA and FTD Software could allow an unauthenticated, remote attacker to cause a cryptographic collision, enabling discovery of the private key of an affected device. The issue is due to insufficient entropy in the DRBG when generating cryptographic keys. An attacker could exploit this by generating many keys and looking for collisions with target devices.
Risk Assessment
The risk includes impersonation of the device or decryption of traffic secured by the affected key, potentially leading to confidentiality and integrity breaches.
Recommendation
It is recommended to upgrade ASA/FTD software to a patched version and regenerate cryptographic keys after the upgrade.
Original NVD description (English source)
A vulnerability in the Deterministic Random Bit Generator (DRBG), also known as Pseudorandom Number Generator (PRNG), used in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a cryptographic collision, enabling the attacker to discover the private key of an affected device. The vulnerability is due to insufficient entropy in the DRBG when generating cryptographic keys. An attacker could exploit this vulnerability by generating a large number of cryptographic keys on an affected device and looking for collisions with target devices. A successful exploit could allow the attacker to impersonate an affected target device or to decrypt traffic secured by an affected key that is sent to or from an affected target device.