CVE-2024-39908

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.

Impact

The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>.

If you need to parse untrusted XMLs, you may be impacted to these vulnerabilities.

Patches

The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities.

Workarounds

Don't parse untrusted XMLs.

References

• https://github.com/ruby/rexml/security/advisories/GHSA-vg3r-rm7w-2xgh : This is a similar vulnerability
• https://www.ruby-lang.org/en/news/2024/07/16/dos-rexml-cve-2024-39908/

Ruby is a fast and easy interpreted scripting language for object-oriented programming. It has many functions for processing text Files and perform system management tasks (such as Perl).

Security Fix(es):

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.(CVE-2024-39908)

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.2 has some DoS vulnerabilities when it parses an XML that has many specific characters such as whitespace character, >] and ]>. The REXML gem 3.3.3 or later include the patches to fix these vulnerabilities.(CVE-2024-41123)

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.6 has a DoS vulnerability when it parses an XML that has many deep elements that have same local name attributes. If you need to parse untrusted XMLs with tree parser API like REXML::Document.new, you may be impacted to this vulnerability. If you use other parser APIs such as stream parser API and SAX2 parser API, this vulnerability is not affected. The REXML gem 3.3.6 or later include the patch to fix the vulnerability.(CVE-2024-43398)

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)

• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)

• rexml: DoS vulnerability in REXML (CVE-2024-41946)

• rexml: DoS vulnerability in REXML (CVE-2024-43398)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)

• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)

• rexml: DoS vulnerability in REXML (CVE-2024-41946)

• rexml: DoS vulnerability in REXML (CVE-2024-43398)

• CGI: ReDoS in CGI::Util#escapeElement (CVE-2025-27220)

• CGI: Denial of Service in CGI::Cookie.parse (CVE-2025-27219)

• uri: userinfo leakage in URI#join, URI#merge and URI#+ (CVE-2025-27221)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)

• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)

• rexml: DoS vulnerability in REXML (CVE-2024-41946)

• rexml: DoS vulnerability in REXML (CVE-2024-43398)

• CGI: ReDoS in CGI::Util#escapeElement (CVE-2025-27220)

• CGI: Denial of Service in CGI::Cookie.parse (CVE-2025-27219)

• uri: userinfo leakage in URI#join, URI#merge and URI#+ (CVE-2025-27221)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)
• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)
• rexml: DoS vulnerability in REXML (CVE-2024-41946)
• rexml: DoS vulnerability in REXML (CVE-2024-43398)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)
• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)
• rexml: DoS vulnerability in REXML (CVE-2024-41946)
• rexml: DoS vulnerability in REXML (CVE-2024-43398)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)
• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)
• rexml: DoS vulnerability in REXML (CVE-2024-41946)
• rexml: DoS vulnerability in REXML (CVE-2024-43398)
• CGI: ReDoS in CGI::Util#escapeElement (CVE-2025-27220)
• CGI: Denial of Service in CGI::Cookie.parse (CVE-2025-27219)
• uri: userinfo leakage in URI#join, URI#merge and URI#+ (CVE-2025-27221)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)
• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)
• rexml: DoS vulnerability in REXML (CVE-2024-41946)
• rexml: DoS vulnerability in REXML (CVE-2024-43398)
• CGI: ReDoS in CGI::Util#escapeElement (CVE-2025-27220)
• CGI: Denial of Service in CGI::Cookie.parse (CVE-2025-27219)
• uri: userinfo leakage in URI#join, URI#merge and URI#+ (CVE-2025-27221)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.

REXML is an XML toolkit for Ruby. The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. If you need to parse untrusted XMLs, you many be impacted to these vulnerabilities. The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. Users are advised to upgrade. Users unable to upgrade should avoid parsing untrusted XML strings.

• CVE-2024-39908: fix performance issue caused by using repeated characters to avoid DoS vulnerabilities when it parses an XML
• CVE-2024-43398: improve namespace conflicted attribute check to avoid DoS vulnerability when it parses an XML

• CVE-2024-39908: fix ReDoS in REXML parser for repeated > / character reference payloads
• CVE-2024-41123: fix ReDoS in REXML source.match when no terminator string is specified
• CVE-2024-41946: add XML entity expansion limit to REXML SAX and pull parsers
• CVE-2024-43398: fix DoS via deep elements with namespace-conflicted attributes in REXML tree parser

The REXML gem before 3.2.6 has a denial of service vulnerability when it parses an XML that has many <s in an attribute value. (CVE-2024-35176) The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as <, 0 and %>. (CVE-2024-39908) The REXML gem before 3.3.2 has some DoS vulnerabilities when it parses an XML that has many specific characters such as whitespace character, >] and ]>. (CVE-2024-41123) The REXML gem 3.3.2 has a DoS vulnerability when it parses an XML that has many entity expansions with SAX2 or pull parser API. (CVE-2024-41946) The REXML gem before 3.3.6 has a DoS vulnerability when it parses an XML that has many deep elements that have same local name attributes. (CVE-2024-43398) The REXML gem before 3.3.9 has a ReDoS vulnerability when it parses an XML that has many digits between &# and x...; in a hex numeric character reference (&#x...;). (CVE-2024-49761)

rubygem-rexml was updated to 3.3.9:

• fixes CVE-2024-49761, CVE-2024-43398, CVE-2024-41946, CVE-2024-41123, CVE-2024-39908, CVE-2024-35176
• bsc#1232440, bsc#1229673, bsc#1228799, bsc#1228794, bsc#1228072, bsc#1224390

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

Security Fix(es):

• rexml: DoS vulnerability in REXML (CVE-2024-39908)

• rexml: rubygem-rexml: DoS when parsing an XML having many specific characters such as whitespace character, >] and ]> (CVE-2024-41123)

• rexml: DoS vulnerability in REXML (CVE-2024-41946)

• rexml: DoS vulnerability in REXML (CVE-2024-43398)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

This update for ruby2.5 fixes the following issues:

• CVE-2024-43398: Fixed DoS when parsing a XML that has many deep elements with the same local name attributes (bsc#1229673)
• CVE-2024-41123: Fixed DoS when parsing an XML that contains many specific characters such as whitespaces, >] and ]> (bsc#1228794)
• CVE-2024-41946: Fixed DoS when parsing an XML that has many entity expansions with SAX2 or pull parser API (bsc#1228799)
• CVE-2024-35176: Fixed DoS when parsing an XML that has many left angled brackets in an attribute value (bsc#1224390)
• CVE-2024-39908: Fixed ReDos when parsing an XML that has many specific characters (bsc#1228072)

It was discovered that Ruby incorrectly handled parsing of an XML document that has specific XML characters in an attribute value using REXML gem. An attacker could use this issue to cause Ruby to crash, resulting in a denial of service. This issue only affected in Ubuntu 22.04 LTS and Ubuntu 24.04 LTS. (CVE-2024-35176, CVE-2024-39908, CVE-2024-41123)

It was discovered that Ruby incorrectly handled parsing of an XML document that has many entity expansions with SAX2 or pull parser API. An attacker could use this issue to cause Ruby to crash, resulting in a denial of service. (CVE-2024-41946)

It was discovered that Ruby incorrectly handled parsing of an XML document that has many digits in a hex numeric character reference. An attacker could use this issue to cause Ruby to crash, resulting in a denial of service. (CVE-2024-49761)

It was discovered that Ruby incorrectly handled parsing of an XML document that has specific XML characters in an attribute value using REXML gem. An attacker could use this issue to cause Ruby to crash, resulting in a denial of service.

It was discovered that Ruby incorrectly handled parsing of an XML document that has specific XML characters in an attribute value using REXML gem. An attacker could use this issue to cause Ruby to crash, resulting in a denial of service. This issue only affected in Ubuntu 22.04 LTS, Ubuntu 24.04 LTS, and Ubuntu 24.10. (CVE-2024-35176, CVE-2024-39908, CVE-2024-41123, CVE-2024-43398)

It was discovered that Ruby incorrectly handled expanding ranges in the net-imap response parser. If a user or automated system were tricked into connecting to a malicious IMAP server, a remote attacker could possibly use this issue to consume memory, leading to a denial of service. This issue only affected Ubuntu 24.04 LTS, and Ubuntu 24.10. (CVE-2025-25186)

It was discovered that the Ruby CGI gem incorrectly handled parsing certain cookies. A remote attacker could possibly use this issue to consume resources, leading to a denial of service. (CVE-2025-27219)

It was discovered that the Ruby CGI gem incorrectly handled parsing certain regular expressions. A remote attacker could possibly use this issue to consume resources, leading to a denial of service. (CVE-2025-27220)

It was discovered that the Ruby URI gem incorrectly handled certain URI handling methods. A remote attacker could possibly use this issue to leak authentication credentials. (CVE-2025-27221)

It was discovered that the REXML module bunded into Ruby incorrectly handled parsing XML documents with repeated instances of certain characters. An attacker could possibly use this issue to cause REXML to consume excessive resources, leading to a denial of service. Ubuntu 18.04 LTS and Ubuntu 20.04 LTS were previously addressed in USN-7256-1 and USN-7734-1. This update addresses the issue in Ubuntu 16.04 LTS. (CVE-2024-35176)

It was discovered that the REXML module bunded into Ruby incorrectly handled parsing XML documents with repeated instances of certain characters. An attacker could possibly use this issue to cause REXML to consume excessive resources, leading to a denial of service. Ubuntu 20.04 LTS was previously addressed in USN-7256-1. This update addresses the issue in Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2024-39908, CVE-2024-41123)

It was discovered that the REXML module bunded into Ruby incorrectly handled parsing XML documents with many entity expansions. An attacker could possibly use this issue to cause REXML to consume excessive resources, leading to a denial of service. Ubuntu 20.04 LTS was previously addressed in USN-7091-2. This update addresses the issue in Ubuntu 16.04 LTS and Ubuntu 18.04 LTS. (CVE-2024-41946)

It was discovered that the WEBrick module bundled into Ruby incorrectly handled having both a Content-Length header and a Transfer-Encoding header. A remote attacker could possibly use this issue to perform a HTTP request smuggling attack. (CVE-2024-47220)

It was discovered that the WEBrick module bundled into Ruby incorrectly parsed HTTP headers. In configurations where the WEBrick module is placed behind an HTTP proxy, a remote attacker could possibly use this issue to perform an HTTP Request Smuggling attack. (CVE-2025-6442)