The FileUtils.remove_entry_secure method in Ruby 1.8.6 through 1.8.6-420, 1.8.7 through 1.8.7-330, 1.8.8dev, 1.9.1 through 1.9.1-430, 1.9.2 through 1.9.2-136, and 1.9.3dev allows local users to delete arbitrary files via a symlink attack.

The remote host is affected by the vulnerability described in GLSA-201412-27 (Ruby: Denial of Service)

    Multiple vulnerabilities have been discovered in Ruby. Please review the       CVE identifiers referenced below for details.
  Impact :

    A context-dependent attacker could possibly execute arbitrary code with       the privileges of the process, cause a Denial of Service condition, or       bypass security restrictions.
  Workaround :

    There is no known workaround at this time.

Ruby was prone to several security issues :

  - a race condition allowed local users to delete arbitrary     files (CVE-2011-1004)

  - exception methods could bypass safe mode (CVE-2011-1005)

  - webrick cross site scripting issue (CVE-2010-0541)

  - memory corruption in the BigDecimal class     (CVE-2011-0188)

The remote Oracle Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2011-0910 advisory.

    - Address CVE-2011-1004 'Symlink race condition by removing directory trees in       fileutils module'
      * ruby-1.8.7-CVE-2011-1004.patch
    - Address CVE-2011-1005 'Untrusted codes able to modify arbitrary strings'
      * ruby-1.8.7-CVE-2011-1005.patch
    - Address CVE-2011-0188 'memory corruption in BigDecimal on 64bit platforms'
      * ruby-1.8.7-CVE-2011-0188.patch

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

From Red Hat Security Advisory 2011:0909 :

Updated ruby packages that fix multiple security issues are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to do system management tasks.

A flaw was found in the way large amounts of memory were allocated on 64-bit systems when using the BigDecimal class. A context-dependent attacker could use this flaw to cause memory corruption, causing a Ruby application that uses the BigDecimal class to crash or, possibly, execute arbitrary code. This issue did not affect 32-bit systems.
(CVE-2011-0188)

A race condition flaw was found in the remove system entries method in the FileUtils module. If a local user ran a Ruby script that uses this method, a local attacker could use this flaw to delete arbitrary files and directories accessible to that user via a symbolic link attack.
(CVE-2011-1004)

It was found that WEBrick (the Ruby HTTP server toolkit) did not filter terminal escape sequences from its log files. A remote attacker could use specially crafted HTTP requests to inject terminal escape sequences into the WEBrick log files. If a victim viewed the log files with a terminal emulator, it could result in control characters being executed with the privileges of that user. (CVE-2009-4492)

A cross-site scripting (XSS) flaw was found in the way WEBrick displayed error pages. A remote attacker could use this flaw to perform a cross-site scripting attack against victims by tricking them into visiting a specially crafted URL. (CVE-2010-0541)

A flaw was found in the method for translating an exception message into a string in the Exception class. A remote attacker could use this flaw to bypass safe level 4 restrictions, allowing untrusted (tainted) code to modify arbitrary, trusted (untainted) strings, which safe level 4 restrictions would otherwise prevent. (CVE-2011-1005)

Red Hat would like to thank Drew Yao of Apple Product Security for reporting the CVE-2011-0188 and CVE-2010-0541 issues.

All Ruby users should upgrade to these updated packages, which contain backported patches to resolve these issues.

Updated ruby packages that fix multiple security issues are now available for Red Hat Enterprise Linux 5.

The Red Hat Security Response Team has rated this update as having moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to do system management tasks.

A flaw was found in the way large amounts of memory were allocated on 64-bit systems when using the BigDecimal class. A context-dependent attacker could use this flaw to cause memory corruption, causing a Ruby application that uses the BigDecimal class to crash or, possibly, execute arbitrary code. This issue did not affect 32-bit systems.
(CVE-2011-0188)

A race condition flaw was found in the remove system entries method in the FileUtils module. If a local user ran a Ruby script that uses this method, a local attacker could use this flaw to delete arbitrary files and directories accessible to that user via a symbolic link attack.
(CVE-2011-1004)

It was found that WEBrick (the Ruby HTTP server toolkit) did not filter terminal escape sequences from its log files. A remote attacker could use specially crafted HTTP requests to inject terminal escape sequences into the WEBrick log files. If a victim viewed the log files with a terminal emulator, it could result in control characters being executed with the privileges of that user. (CVE-2009-4492)

A cross-site scripting (XSS) flaw was found in the way WEBrick displayed error pages. A remote attacker could use this flaw to perform a cross-site scripting attack against victims by tricking them into visiting a specially crafted URL. (CVE-2010-0541)

A flaw was found in the method for translating an exception message into a string in the Exception class. A remote attacker could use this flaw to bypass safe level 4 restrictions, allowing untrusted (tainted) code to modify arbitrary, trusted (untainted) strings, which safe level 4 restrictions would otherwise prevent. (CVE-2011-1005)

Red Hat would like to thank Drew Yao of Apple Product Security for reporting the CVE-2011-0188 and CVE-2010-0541 issues.

All Ruby users should upgrade to these updated packages, which contain backported patches to resolve these issues.

Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to do system management tasks.

A flaw was found in the way large amounts of memory were allocated on 64-bit systems when using the BigDecimal class. A context-dependent attacker could use this flaw to cause memory corruption, causing a Ruby application that uses the BigDecimal class to crash or, possibly, execute arbitrary code. This issue did not affect 32-bit systems.
(CVE-2011-0188)

A race condition flaw was found in the remove system entries method in the FileUtils module. If a local user ran a Ruby script that uses this method, a local attacker could use this flaw to delete arbitrary files and directories accessible to that user via a symbolic link attack.
(CVE-2011-1004)

A flaw was found in the method for translating an exception message into a string in the Exception class. A remote attacker could use this flaw to bypass safe level 4 restrictions, allowing untrusted (tainted) code to modify arbitrary, trusted (untainted) strings, which safe level 4 restrictions would otherwise prevent. (CVE-2011-1005)

All Ruby users should upgrade to these updated packages, which contain backported patches to resolve these issues.

Ruby is an extensible, interpreted, object-oriented, scripting language. It has features to process text files and to do system management tasks.

A flaw was found in the way large amounts of memory were allocated on 64-bit systems when using the BigDecimal class. A context-dependent attacker could use this flaw to cause memory corruption, causing a Ruby application that uses the BigDecimal class to crash or, possibly, execute arbitrary code. This issue did not affect 32-bit systems.
(CVE-2011-0188)

A race condition flaw was found in the remove system entries method in the FileUtils module. If a local user ran a Ruby script that uses this method, a local attacker could use this flaw to delete arbitrary files and directories accessible to that user via a symbolic link attack.
(CVE-2011-1004)

It was found that WEBrick (the Ruby HTTP server toolkit) did not filter terminal escape sequences from its log files. A remote attacker could use specially crafted HTTP requests to inject terminal escape sequences into the WEBrick log files. If a victim viewed the log files with a terminal emulator, it could result in control characters being executed with the privileges of that user. (CVE-2009-4492)

A cross-site scripting (XSS) flaw was found in the way WEBrick displayed error pages. A remote attacker could use this flaw to perform a cross-site scripting attack against victims by tricking them into visiting a specially crafted URL. (CVE-2010-0541)

A flaw was found in the method for translating an exception message into a string in the Exception class. A remote attacker could use this flaw to bypass safe level 4 restrictions, allowing untrusted (tainted) code to modify arbitrary, trusted (untainted) strings, which safe level 4 restrictions would otherwise prevent. (CVE-2011-1005)

All Ruby users should upgrade to these updated packages, which contain backported patches to resolve these issues.

The remote host is running a version of Mac OS X 10.7 that is older than version 10.7.4.  The newer version contains numerous security-related fixes for the following components :

  - Login Windows
  - Bluetooth
  - curl
  - HFS
  - Kernel
  - libarchive
  - libsecurity
  - libxml
  - LoginUIFramework
  - PHP
  - Quartz Composer
  - QuickTime
  - Ruby
  - Security Framework
  - Time Machine
  - X11

The remote host is running a version of Mac OS X 10.6 that does not have Security Update 2012-002 applied. This update contains multiple security-related fixes for the following components :

  - curl
  - Directory Service
  - ImageIO
  - libarchive
  - libsecurity
  - libxml
  - Quartz Composer
  - QuickTime
  - Ruby
  - Samba
  - Security Framework

The remote host is running a version of Mac OS X 10.7.x that is prior to 10.7.4. The newer version contains numerous security-related fixes for the following components :

  - Login Window
  - Bluetooth
  - curl
  - HFS
  - Kernel
  - libarchive
  - libsecurity
  - libxml
  - LoginUIFramework
  - PHP
  - Quartz Composer
  - QuickTime
  - Ruby
  - Security Framework
  - Time Machine
  - X11

Note that this update addresses the recent FileVault password vulnerability, in which user passwords are stored in plaintext to a system-wide debug log if the legacy version of FileVault is used to encrypt user directories after a system upgrade to Lion. Since the patch only limits further exposure, though, we recommend that all users on the system change their passwords if user folders were encrypted using the legacy version of FileVault prior to and after an upgrade to OS X 10.7.

Drew Yao discovered that the WEBrick HTTP server was vulnerable to cross-site scripting attacks when displaying error pages. A remote attacker could use this flaw to run arbitrary web script.
(CVE-2010-0541)

Drew Yao discovered that Ruby's BigDecimal module did not properly allocate memory on 64-bit platforms. An attacker could use this flaw to cause a denial of service or possibly execute arbitrary code with user privileges. (CVE-2011-0188)

Nicholas Jefferson discovered that the FileUtils.remove_entry_secure method in Ruby did not properly remove non-empty directories. An attacker could use this flaw to possibly delete arbitrary files.
(CVE-2011-1004)

It was discovered that Ruby incorrectly allowed untainted strings to be modified in protective safe levels. An attacker could use this flaw to bypass intended access restrictions. (CVE-2011-1005)

Eric Wong discovered that Ruby does not properly reseed its pseudorandom number generator when creating child processes. An attacker could use this flaw to gain knowledge of the random numbers used in other Ruby child processes. (CVE-2011-2686)

Eric Wong discovered that the SecureRandom module in Ruby did not properly seed its pseudorandom number generator. An attacker could use this flaw to gain knowledge of the random numbers used by another Ruby process with the same process ID number. (CVE-2011-2705)

Alexander Klink and Julian Walde discovered that Ruby computed hash values without restricting the ability to trigger hash collisions predictably. A remote attacker could cause a denial of service by crafting values used in hash tables. (CVE-2011-4815).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The remote Redhat Enterprise Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2011:0910 advisory.

  - ruby: memory corruption in BigDecimal on 64bit platforms (CVE-2011-0188)

  - Ruby: Symlink race condition by removing directory trees in fileutils module (CVE-2011-1004)

  - Ruby: Untrusted codes able to modify arbitrary strings (CVE-2011-1005)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Redhat Enterprise Linux 5 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2011:0909 advisory.

  - ruby WEBrick log escape sequence (CVE-2009-4492)

  - Ruby WEBrick javascript injection flaw (CVE-2010-0541)

  - ruby: memory corruption in BigDecimal on 64bit platforms (CVE-2011-0188)

  - Ruby: Symlink race condition by removing directory trees in fileutils module (CVE-2011-1004)

  - Ruby: Untrusted codes able to modify arbitrary strings (CVE-2011-1005)

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The following several security issues of ruby have been fixed :

  - A race condition allowing local users to delete     arbitrary files. (CVE-2011-1004)

  - Exception methods could bypass safe mode.
    (CVE-2011-1005)

  - webrick does not sanitize non-printable characters in     log. (CVE-2009-4492)

  - A webrick cross-site scripting issue. (CVE-2010-0541)

  - A memory corruption in the BigDecimal class     (CVE-2011-0188)

Multiple vulnerabilities have been identified and fixed in ruby :

Cross-site scripting (XSS) vulnerability in the WEBrick HTTP server in Ruby allows remote attackers to inject arbitrary web script or HTML via a crafted URI that triggers a UTF-7 error page (CVE-2010-0541).

The FileUtils.remove_entry_secure method in Ruby allows local users to delete arbitrary files via a symlink attack (CVE-2011-1004).

The safe-level feature in Ruby allows context-dependent attackers to modify strings via the Exception#to_s method, as demonstrated by changing an intended pathname (CVE-2011-1005).

The VpMemAlloc function in bigdecimal.c in the BigDecimal class in Ruby does not properly allocate memory, which allows context-dependent attackers to execute arbitrary code or cause a denial of service (application crash) via vectors involving creation of a large BigDecimal value within a 64-bit process, related to an integer truncation issue. (CVE-2011-0188).

Packages for 2009.0 are provided as of the Extended Maintenance Program. Please visit this link to learn more:
http://store.mandriva.com/product_info.php?cPath=149 products_id=490

The updated packages have been patched to correct this issue.

Two patches backported from 1.8.7 branch, for

  - Symlink race condition in FileUtils.remove_entry_secure

  - bypass of $SAFE mechanism in Exception#to_s

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

ID	Name	Product	Family	Severity
79980	GLSA-201412-27 : Ruby: Denial of Service	Nessus	Gentoo Local Security Checks	high
75729	openSUSE Security Update : ruby (openSUSE-SU-2011:0561-1)	Nessus	SuSE Local Security Checks	medium
68299	Oracle Linux 6 : ruby (ELSA-2011-0910)	Nessus	Oracle Linux Local Security Checks	critical
68298	Oracle Linux 5 : ruby (ELSA-2011-0909)	Nessus	Oracle Linux Local Security Checks	medium
67085	CentOS 5 : ruby (CESA-2011:0909)	Nessus	CentOS Local Security Checks	medium
61077	Scientific Linux Security Update : ruby on SL6.x i386/x86_64	Nessus	Scientific Linux Local Security Checks	medium
61076	Scientific Linux Security Update : ruby on SL5.x i386/x86_64	Nessus	Scientific Linux Local Security Checks	medium
6482	Mac OS X 10.7 < 10.7.4 Multiple Vulnerabilities	Nessus Network Monitor	Generic	critical
59067	Mac OS X Multiple Vulnerabilities (Security Update 2012-002) (BEAST)	Nessus	MacOS X Local Security Checks	critical
59066	Mac OS X 10.7.x < 10.7.4 Multiple Vulnerabilities (BEAST)	Nessus	MacOS X Local Security Checks	critical
58146	Ubuntu 10.04 LTS / 10.10 / 11.04 / 11.10 : ruby1.8 vulnerabilities (USN-1377-1)	Nessus	Ubuntu Local Security Checks	high
55452	RHEL 6 : ruby (RHSA-2011:0910)	Nessus	Red Hat Local Security Checks	critical
55451	RHEL 5 : ruby (RHSA-2011:0909)	Nessus	Red Hat Local Security Checks	critical
54921	SuSE 11.1 Security Update : ruby (SAT Patch Number 4585)	Nessus	SuSE Local Security Checks	medium
54626	Mandriva Linux Security Advisory : ruby (MDVSA-2011:097)	Nessus	Mandriva Local Security Checks	medium
52485	Fedora 13 : ruby-1.8.6.420-2.fc13 (2011-1913)	Nessus	Fedora Local Security Checks	medium

Detections

Analytics

CVE-2011-1004

medium

Tenable Plugins

high

medium

critical

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critical

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