Ruby: Multiple vulnerabilities — GLSA 200812-17

Multiple vulnerabilities have been discovered in Ruby that allow for attacks including arbitrary code execution and Denial of Service.

Affected Packages

dev-lang/ruby on all architectures
Affected versions < 1.8.6_p287-r1
Unaffected versions >= 1.8.6_p287-r1

Background

Ruby is an interpreted object-oriented programming language. The elaborate standard library includes an HTTP server ("WEBRick") and a class for XML parsing ("REXML").

Description

Multiple vulnerabilities have been discovered in the Ruby interpreter and its standard libraries. Drew Yao of Apple Product Security discovered the following flaws:

  • Arbitrary code execution or Denial of Service (memory corruption) in the rb_str_buf_append() function (CVE-2008-2662).
  • Arbitrary code execution or Denial of Service (memory corruption) in the rb_ary_stor() function (CVE-2008-2663).
  • Memory corruption via alloca in the rb_str_format() function (CVE-2008-2664).
  • Memory corruption ("REALLOC_N") in the rb_ary_splice() and rb_ary_replace() functions (CVE-2008-2725).
  • Memory corruption ("beg + rlen") in the rb_ary_splice() and rb_ary_replace() functions (CVE-2008-2726).

Furthermore, several other vulnerabilities have been reported:

  • Tanaka Akira reported an issue with resolv.rb that enables attackers to spoof DNS responses (CVE-2008-1447).
  • Akira Tagoh of RedHat discovered a Denial of Service (crash) issue in the rb_ary_fill() function in array.c (CVE-2008-2376).
  • Several safe level bypass vulnerabilities were discovered and reported by Keita Yamaguchi (CVE-2008-3655).
  • Christian Neukirchen is credited for discovering a Denial of Service (CPU consumption) attack in the WEBRick HTTP server (CVE-2008-3656).
  • A fault in the dl module allowed the circumvention of taintness checks which could possibly lead to insecure code execution was reported by "sheepman" (CVE-2008-3657).
  • Tanaka Akira again found a DNS spoofing vulnerability caused by the resolv.rb implementation using poor randomness (CVE-2008-3905).
  • Luka Treiber and Mitja Kolsek (ACROS Security) disclosed a Denial of Service (CPU consumption) vulnerability in the REXML module when dealing with recursive entity expansion (CVE-2008-3790).

Impact

These vulnerabilities allow remote attackers to execute arbitrary code, spoof DNS responses, bypass Ruby's built-in security and taintness checks, and cause a Denial of Service via crash or CPU exhaustion.

Workaround

There is no known workaround at this time.

Resolution

All Ruby users should upgrade to the latest version:

 # emerge --sync
 # emerge --ask --oneshot --verbose ">=dev-lang/ruby-1.8.6_p287-r1"

References

Release Date
December 16, 2008

Latest Revision
December 16, 2008: 01

Severity
normal

Exploitable
remote

Bugzilla entries