[SOLR-13750] [CVE-2019-12401] XML Bomb in Apache Solr versions prior to 5.0.0

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Information Provided
• Affects Version/s: 1.3, 1.4, 1.4.1, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.6.1, 3.6.2, 4.0, 4.1, 4.2, 4.2.1, 4.3, 4.3.1, 4.4, 4.5, 4.5.1, 4.6, 4.6.1, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1, 4.9, 4.9.1, 4.10, 4.10.1, 4.10.2, 4.10.3, 4.10.4
• Fix Version/s: 5.0
• Assignee: Unassigned
• Reporter: Tomas Eduardo Fernandez Lobbe
• Created: 09/Sep/19 19:10
• Updated: 21/Jan/20 16:57
• Resolved: 09/Sep/19 22:07

Description

Severity: Medium

Vendor: The Apache Software Foundation

Versions Affected:
1.3.0 to 1.4.1
3.1.0 to 3.6.2
4.0.0 to 4.10.4

Description:
Solr versions prior to 5.0.0 are vulnerable to an XML resource consumption attack (a.k.a. Lol Bomb) via it’s update handler.
By leveraging XML DOCTYPE and ENTITY type elements, the attacker can create a pattern that will expand when the server parses the XML causing OOMs.

Mitigation:

• Upgrade to Apache Solr 5.0 or later.
• Ensure your network settings are configured so that only trusted traffic is allowed to post documents to the running Solr instances.

Credit:
Matei "Mal" Badanoiu