The initialize method in the Histogram class in lib/colorscore/histogram.rb in the colorscore gem before 0.0.5 for Ruby allows context-dependent attackers to execute arbitrary code via shell metacharacters in the (1) image_path, (2) colors, or (3) depth variable.

References

• https://nvd.nist.gov/vuln/detail/CVE-2015-7541
• quadule/colorscore@570b5e8
• http://rubysec.com/advisories/CVE-2015-7541/
• http://www.openwall.com/lists/oss-security/2016/01/05/2
• https://github.com/rubysec/ruby-advisory-db/blob/master/gems/colorscore/CVE-2015-7541.yml
• http://seclists.org/oss-sec/2016/q1/17