CVE-2015-0837

Description

From CVE.org

The mpi_powm function in Libgcrypt before 1.6.3 and GnuPG before 1.4.19 allows attackers to obtain sensitive information by leveraging timing differences when accessing a pre-computed table during modular exponentiation, related to a "Last-Level Cache Side-Channel Attack."

Statement

Red Hat Product Security has rated this issue as having low security impact, a future update may address this flaw in the libgcrypt and gnupg2 packages.

The attack leading to this flaw, is difficult to conduct in practice especially for cross-vm environments, mainly because the attacker needs to run their timing attack script at the exact same time decryption runs on the victim machine. Also this is essentially a chosen ciphertext attack because the attacker provides the ciphertext which the victim needs to be decrypt. Such actions only work when there is sufficient social engineer involved.

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 Score1.24.3N/A
Attack VectorLocalNetworkN/A
Access ComplexityHighMediumN/A
AuthenticationNoneNoneN/A
Confidentiality ImpactPartialPartialN/A
Integrity ImpactNoneNoneN/A
Availability ImpactNoneNoneN/A

Vector

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

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

Frequently Asked Questions

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