CVE-2020-25658 : Security Advisory and Response

Python-rsa is vulnerable to Bleichenbacher timing attacks, allowing attackers to decrypt parts of the cipher text encrypted with RSA.

Understanding CVE-2020-25658

What is CVE-2020-25658?

Python-rsa is susceptible to a specific type of timing attack known as Bleichenbacher attacks, which can be exploited through the RSA decryption API.

The Impact of CVE-2020-25658

This vulnerability has a high severity level with a CVSS base score of 7.5, affecting confidentiality.

Technical Details of CVE-2020-25658

Vulnerability Description

The vulnerability in python-rsa allows attackers to perform Bleichenbacher timing attacks, compromising RSA decryption.

Affected Systems and Versions

Product: python-rsa
Vendor: Sybren A. Stüvel
Versions affected: after 3.0 (inclusive)

Exploitation Mechanism

The flaw can be exploited by attackers using the RSA decryption API to decrypt parts of the cipher text encrypted with RSA.

Mitigation and Prevention

Immediate Steps to Take

Update python-rsa to a non-vulnerable version.
Monitor for any unauthorized decryption activities.

Long-Term Security Practices

Implement secure coding practices to prevent similar vulnerabilities.
Regularly review and update cryptographic libraries and dependencies.

Patching and Updates

Apply patches provided by the vendor to address the vulnerability.