CVE-2015-0204: OpenSSL client RSA-to-EXPORT_RSA downgrade (FREAK)

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 17 September 2026. Confidence: medium.

high priorityThe flaw enables decryption of affected client TLS sessions and carries a very high EPSS score, though CVSS v2 rates it only medium and no KEV listing or known exploit tags are present.

What it is

The ssl3_get_key_exchange function in OpenSSL client code accepts a weak ephemeral RSA key offered by a server in a noncompliant role, allowing an RSA-to-EXPORT_RSA downgrade. This is the client-side FREAK issue; the CVE scope is limited to OpenSSL-based client code, not server-side EXPORT_RSA or other TLS implementations.

Impact

An attacker positioned to influence the TLS handshake can force the client to negotiate export-grade RSA, weakening the session key enough to facilitate brute-force decryption of the connection.

Attack surface

Reached over the network during the TLS handshake when an OpenSSL-based client connects to a malicious or compromised server; no authentication is required, but the attack depends on the client initiating a connection to the attacker-controlled endpoint.

Exploitation

Not listed in CISA KEV and no ransomware associations are documented; EPSS is very high (0.98685, 99.923rd percentile), indicating elevated predicted exploitation activity, though the references carry no exploit tags.

What to do

• Upgrade OpenSSL client code to 0.9.8zd, 1.0.0p, 1.0.1k or later as applicable to the deployed branch.
• Disable or remove EXPORT-grade cipher suites from client configurations where the platform allows it.
• Inventory and update applications and appliances that embed OpenSSL client libraries, since patching the OS package alone may not cover them.
• Apply vendor advisories for affected downstream products (for example Juniper, Apple, openSUSE) that bundle the vulnerable OpenSSL client code.

Detection

• Monitor TLS handshakes for negotiation of EXPORT_RSA cipher suites or unusually small ephemeral RSA keys.
• Alert on client connections to servers presenting export-grade RSA parameters, especially from internal hosts to untrusted endpoints.
• Track OpenSSL client library versions across hosts and flag those below the fixed releases.

This assessment is produced automatically and is not human-reviewed. Verify against the vendor advisory before acting on it.