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MEDIUM

libgcrypt: last-level cache side-channel attack

Published Nov 29, 2019

Description

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."

Affected products

Remediation

Red Hat 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.

Metrics

Weaknesses (1)

References (9)

Change history (0)

No recorded changes yet.

Sources
CVE.org / MITRE
Status PUBLISHED
Assigner debian
Published Nov 29, 2019
Updated Aug 6, 2024
Reserved Jan 7, 2015
NVD
Status Modified
Modified Jun 17, 2026
Red Hat
Severity Low
Public date Feb 27, 2015