SB2017011128 - Gentoo update for Botan



SB2017011128 - Gentoo update for Botan

Published: January 11, 2017 Updated: January 11, 2017

Security Bulletin ID SB2017011128
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 2
Exploitation vector Remote access
Highest impact Information disclosure

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 2 vulnerabilities.


1) Information disclosure (CVE-ID: CVE-2016-2849)

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote non-authenticated attacker to gain access to sensitive information.

Botan before 1.10.13 and 1.11.x before 1.11.29 do not use a constant-time algorithm to perform a modular inverse on the signature nonce k, which might allow remote attackers to obtain ECDSA secret keys via a timing side-channel attack.


2) Input validation error (CVE-ID: CVE-2016-2850)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote non-authenticated attacker to manipulate data.

Botan 1.11.x before 1.11.29 does not enforce TLS policy for (1) signature algorithms and (2) ECC curves, which allows remote attackers to conduct downgrade attacks via unspecified vectors.


Remediation

Install update from vendor's website.