CVE-2024-2467 identifies a timing-based side-channel vulnerability in the perl-Crypt-OpenSSL-RSA package, specifically targeting the legacy PKCS#1v1.5 RSA encryption padding mode. This vulnerability enables a Bleichenbacher-style attack, where an attacker can recover plaintext by analyzing timing discrepancies during decryption operations. The attack requires the ability to send a large number of trial ciphertexts over a network and observe the timing responses, exploiting subtle differences in processing time to infer information about the plaintext. The vulnerability does not require privileges or user interaction but has a high attack complexity due to the need for extensive trial messages and precise timing measurements. The CVSS 3.1 score of 5.9 reflects a medium severity, with a high impact on confidentiality but no effect on integrity or availability. No known public exploits exist yet, but the flaw affects any system using the vulnerable perl package with legacy PKCS#1v1.5 padding, which remains in use in some legacy systems and applications. The flaw stems from the inherent weaknesses of the PKCS#1v1.5 padding scheme, which has been deprecated in favor of more secure alternatives like RSA-OAEP. The perl-Crypt-OpenSSL-RSA package is commonly used in cryptographic operations within perl applications, and this vulnerability could expose sensitive encrypted data if exploited. The attack's feasibility depends on network access and the ability to send numerous decryption requests, making it more relevant to exposed services or APIs using this cryptographic method.

For European organizations, the primary impact of CVE-2024-2467 lies in the potential compromise of confidentiality for data encrypted using the vulnerable perl-Crypt-OpenSSL-RSA package with PKCS#1v1.5 padding. Sensitive information such as personal data, intellectual property, or cryptographic keys could be exposed if an attacker successfully performs the Bleichenbacher-style attack. This is particularly concerning for sectors like finance, healthcare, government, and critical infrastructure, where encrypted communications and data protection are paramount. The attack does not affect data integrity or system availability, but the breach of confidentiality could lead to regulatory non-compliance under GDPR and other data protection laws, resulting in legal and financial repercussions. The medium severity indicates that while the risk is not immediate or trivial, it requires attention, especially in environments where legacy cryptographic implementations persist. The necessity for a high volume of trial messages and network access limits the attack surface but does not eliminate risk for externally facing services or poorly segmented internal networks. Organizations relying on perl-based cryptographic libraries for legacy systems may face increased exposure until mitigations are applied.

To mitigate CVE-2024-2467 effectively, European organizations should: 1) Transition away from the vulnerable PKCS#1v1.5 RSA padding to modern, secure padding schemes such as RSA-OAEP, which are resistant to Bleichenbacher-style attacks. 2) Audit and inventory all systems and applications using the perl-Crypt-OpenSSL-RSA package to identify vulnerable instances. 3) Apply patches or updates to the perl-Crypt-OpenSSL-RSA package as they become available from maintainers or consider replacing the package with alternatives that do not use legacy padding. 4) Implement network-level protections such as rate limiting and anomaly detection to prevent or detect large volumes of trial decryption requests indicative of an attack. 5) Employ cryptographic best practices, including using TLS 1.3 or higher for encrypted communications, which do not rely on vulnerable padding schemes. 6) Conduct regular security assessments and penetration tests focusing on cryptographic implementations to identify and remediate weaknesses. 7) Educate developers and system administrators about the risks of legacy cryptographic schemes and encourage migration to modern standards. These steps will reduce the attack surface and protect sensitive data from timing-based side-channel exploits.