CVE-2015-0285

Description

From CVE.org

The ssl3_client_hello function in s3_clnt.c in OpenSSL 1.0.2 before 1.0.2a does not ensure that the PRNG is seeded before proceeding with a handshake, which makes it easier for remote attackers to defeat cryptographic protection mechanisms by sniffing the network and then conducting a brute-force attack.

Statement

This issue did not affect the versions of openssl as shipped with Red Hat Enterprise Linux 5, 6, and 7.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v2 Score Breakdown

Red HatNVDcve.org
Base Score2.64.3N/A
Attack VectorNetworkNetworkN/A
Access ComplexityHighMediumN/A
AuthenticationNoneNoneN/A
Confidentiality ImpactPartialPartialN/A
Integrity ImpactNoneNoneN/A
Availability ImpactNoneNoneN/A

Vector

Red Hat: AV:N/AC:H/Au:N/C:P/I:N/A:N

NVD: AV:N/AC:M/Au:N/C:P/I:N/A:N

Understanding the Weakness (CWE)

Access Control,Other

Technical Impact: Bypass Protection Mechanism; Other

If a PRNG is used incorrectly, such as using the same seed for each initialization or using a predictable seed, then an attacker may be able to easily guess the seed and thus the random numbers. This could lead to unauthorized access to a system if the seed is used for authentication and authorization.

Acknowledgements

Red Hat would like to thank OpenSSL project for reporting this issue. Upstream acknowledges Matt Caswell (OpenSSL development team) as the original reporter.

Frequently Asked Questions

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