CVE-2014-0224: OpenSSL ChangeCipherSpec handling flaw enables MITM session hijack

Automated analysis

Generated by VULONE's analysis model from the NVD record, CISA KEV and EPSS data on 18 September 2026. Confidence: medium.

high priorityCVSS 3.1 is 7.4 (HIGH) with high confidentiality and integrity impact, and EPSS is near the top of the distribution, though no KEV listing or confirmed in-the-wild exploitation is provided.

What it is

OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h does not properly restrict processing of ChangeCipherSpec messages. A man-in-the-middle can force use of a zero-length master key in OpenSSL-to-OpenSSL TLS communications, allowing session hijacking or disclosure of sensitive data. The flaw is known as CCS Injection.

Impact

An attacker positioned in the network path can decrypt or manipulate traffic and hijack affected TLS sessions. Both confidentiality and integrity are impacted; availability is not.

Attack surface

Reached over the network via a crafted TLS handshake; no authentication or user interaction is required, but the attacker must be able to intercept the connection (MITM position). The description scopes the key-derivation weakness to OpenSSL-to-OpenSSL communications.

Exploitation

Not listed in CISA KEV and no ransomware usage is documented, but EPSS is very high (0.95326 probability, 0.99863 percentile), indicating strong likelihood of attempted exploitation. Reference tags are advisory-only and do not confirm in-the-wild exploitation.

What to do

• Upgrade OpenSSL to 0.9.8za, 1.0.0m, 1.0.1h or later, or apply the vendor patch for your distribution.
• Patch or replace dependent products listed as affected (JBoss, MariaDB, Python, Node.js, FileZilla Server, Siemens firmware, and others) using vendor advisories.
• Disable or restrict TLS versions and cipher suites that permit the vulnerable handshake behavior where operationally possible.
• Enforce certificate validation and avoid connecting through untrusted or unauthenticated network paths to reduce MITM exposure.
• Inventory TLS endpoints and embedded devices that may still run unpatched OpenSSL builds.

Detection

• Inspect TLS handshake logs for unexpected or repeated ChangeCipherSpec messages before key exchange completes.
• Monitor for anomalous TLS session resumption or key material behavior on OpenSSL endpoints.
• Use network IDS signatures for CCS Injection handshake patterns if available.
• Correlate endpoint OpenSSL version data against the fixed versions to find unpatched hosts.

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