SB2015080406 - Amazon Linux AMI update for libgcrypt
Published: August 4, 2015
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 4 secuirty vulnerabilities.
1) Credentials management (CVE-ID: CVE-2013-4576)
The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.
GnuPG 1.x before 1.4.16 generates RSA keys using sequences of introductions with certain patterns that introduce a side channel, which allows physically proximate attackers to extract RSA keys via a chosen-ciphertext attack and acoustic cryptanalysis during decryption. NOTE: applications are not typically expected to protect themselves from acoustic side-channel attacks, since this is arguably the responsibility of the physical device. Accordingly, issues of this type would not normally receive a CVE identifier. However, for this issue, the developer has specified a security policy in which GnuPG should offer side-channel resistance, and developer-specified security-policy violations are within the scope of CVE.
2) Information disclosure (CVE-ID: CVE-2014-3591)
The vulnerability allows a local non-authenticated attacker to gain access to sensitive information.
Libgcrypt before 1.6.3 and GnuPG before 1.4.19 does not implement ciphertext blinding for Elgamal decryption, which allows physically proximate attackers to obtain the server's private key by determining factors using crafted ciphertext and the fluctuations in the electromagnetic field during multiplication.
3) Information disclosure (CVE-ID: CVE-2014-5270)
The vulnerability allows a local non-authenticated attacker to gain access to sensitive information.
Libgcrypt before 1.5.4, as used in GnuPG and other products, does not properly perform ciphertext normalization and ciphertext randomization, which makes it easier for physically proximate attackers to conduct key-extraction attacks by leveraging the ability to collect voltage data from exposed metal, a different vector than CVE-2013-4576.
4) Input validation error (CVE-ID: CVE-2015-0837)
The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.
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."
Remediation
Install update from vendor's website.