SB2017092404 - Gentoo update for Mercurial

Description

This security bulletin contains information about 3 vulnerabilities.

1) Link following (CVE-ID: CVE-2017-1000115)

CWE-ID: CWE-59 - Improper Link Resolution Before File Access ('Link Following')

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.

Mercurial prior to version 4.3 is vulnerable to a missing symlink check that can malicious repositories to modify files outside the repository

2) OS Command Injection (CVE-ID: CVE-2017-1000116)

CWE-ID: CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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

The vulnerability allows a remote non-authenticated attacker to execute arbitrary code.

Mercurial prior to 4.3 did not adequately sanitize hostnames passed to ssh, leading to possible shell-injection attacks.

3) Remote code execution (CVE-ID: CVE-2017-9462)

CWE-ID: CWE-20 - Improper input validation

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

The vulnerability allows a remote authenticated attacker to execute arbitrary code on the target system.

The weakness exists due to improper input validation in "hg serve --stdio". A remote attacker can use --debugger as a repository name and consequently execute arbitrary code with privileges of the current user.

Successful exploitation of the vulnerability may result in system compromise.

Remediation

Install update from vendor's website.

References

• https://security.gentoo.org/
• https://security.gentoo.org/glsa/201709-18