Package Instance

REXML round-trip instability
The REXML gem before 3.2.5 in Ruby before 2.6.7, 2.7.x before 2.7.3, and 3.x before 3.0.1 does not properly address XML round-trip issues. An incorrect document can be produced after parsing and serializing.

REXML contains a denial of service vulnerability
### Impact

The REXML gem before 3.2.6 has a DoS vulnerability when it parses an XML that has many `>`s in an attribute value.

If you need to parse untrusted XMLs, you may be impacted to this vulnerability.

### Patches

The REXML gem 3.2.7 or later include the patch to fix this vulnerability.

### Workarounds

Don't parse untrusted XMLs.

### References

* https://www.ruby-lang.org/en/news/2024/05/16/dos-rexml-cve-2024-35176/

REXML denial of service vulnerability
### Impact

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.

### Patches

The REXML gem 3.3.6 or later include the patch to fix the vulnerability.

### Workarounds

Don't parse untrusted XMLs with tree parser API.

### References

* https://www.ruby-lang.org/en/news/2024/08/22/dos-rexml-cve-2024-43398/ : An announce on www.ruby-lang.org

REXML DoS vulnerability
### Impact

The REXML gem before 3.3.2 has a DoS vulnerability when it parses an XML that has many entity expansions with SAX2 or pull parser API.

If you need to parse untrusted XMLs with SAX2 or pull parser API, you may be impacted to this vulnerability.

### Patches

The REXML gem 3.3.3 or later include the patch to fix the vulnerability.

### Workarounds

Don't parse untrusted XMLs with SAX2 or pull parser API.

### References

* https://www.ruby-lang.org/en/news/2008/08/23/dos-vulnerability-in-rexml/ : This is a similar vulnerability
* https://www.ruby-lang.org/en/news/2024/08/01/dos-rexml-cve-2024-41946/: An announce on www.ruby-lang.org

REXML ReDoS vulnerability
### Impact

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...;`).

This does not happen with Ruby 3.2 or later. Ruby 3.1 is the only affected maintained Ruby. Note that Ruby 3.1 will reach EOL on 2025-03.

### Patches

The REXML gem 3.3.9 or later include the patch to fix the vulnerability.

### Workarounds

Use Ruby 3.2 or later instead of Ruby 3.1.

### References

* https://www.ruby-lang.org/en/news/2024/10/28/redos-rexml-cve-2024-49761/: An announce on www.ruby-lang.org

REXML denial of service vulnerability
### 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/