CVE-2021-44548: Solr parent Path Traversal Vulnerability

CRITICAL
Advisory Identifier: GHSA-pccr-q7v9-5f27
Share
CVSS 9.8
CWE-40 CWE-20 CWE-22
Published
Advisory Summary

CVE-2021-44548 is a CRITICAL (CVSS 9.8) path traversal vulnerability (CWE-40: Path Traversal: '\\UNC\share\name\' (Windows UNC Share)) affecting Solr parent libraries in the Maven ecosystem. The issue involves apache solr improper input validation and path traversal. Remediation is available by upgrading affected packages to version 8.11.1.

CVE-2021-44548 at a Glance

CVE Identifier CVE-2021-44548
GHSA Identifier GHSA-pccr-q7v9-5f27
Severity CRITICAL
CVSS v3.1 Base Score 9.8
CWE Classification CWE-40: Path Traversal: '\\UNC\share\name\' (Windows UNC Share)
Affected Product Solr parent
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 9.8

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2021-44548

To remediate this vulnerability, upgrade all affected Solr parent dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

org.apache.solr:solr-parent fixed: 8.11.1 
<dependency>
    <groupId>org.apache.solr</groupId>
    <artifactId>solr-parent</artifactId>
    <version>8.11.1</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=org.apache.solr

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2021-44548, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=org.apache.solr

Analyze the terminal output to locate any version of Solr parent in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 8.11.1), your application is affected.

Note: The mvn dependency:tree -Dincludes=org.apache.solr command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-40: Path Traversal: '\\UNC\share\name\' (Windows UNC Share), where the product accepts input that identifies a windows unc share ('\\unc\share\name') that potentially redirects access to an unintended location or arbitrary file. In Solr parent, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

An Improper Input Validation vulnerability in DataImportHandler of Apache Solr allows an attacker to provide a Windows UNC path resulting in an SMB network call being made from the Solr host to another host on the network. If the attacker has wider access to the network, this may lead to SMB attacks, which may result in: * The exfiltration of sensitive data such as OS user hashes (NTLM/LM hashes), * In case of misconfigured systems, SMB Relay Attacks which can lead to user impersonation on SMB Shares or, in a worse-case scenario, Remote Code Execution This issue affects all Apache Solr versions prior to 8.11.1. This issue only affects Windows.

CVE-2021-44548 Affected Solr parent Versions

1 component(s)
Fixed Versions:
8.11.1
Product / Package Ecosystem Affected Versions Fixed Version
org.apache.solr:solr-parent
maven/org.apache.solr/solr-parent
Maven
< 8.11.1
8.11.1

References

NVD — CVE-2021-44548 NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-44548
Solr parent Source Repository REPOSITORY
https://github.com/apache/solr
Solr parent Security Information SECURITY
https://security.netapp.com/advisory/ntap-20220114-0005
Solr parent Security Information SECURITY
https://solr.apache.org/security.html#cve-2021-44548-apache-solr-information-disclosure-vulnerability-through-dataimporthandler

Frequently Asked Questions

What is CVE-2021-44548?
CVE-2021-44548 is a security vulnerability in Solr parent involving Apache Solr Improper Input Validation and Path Traversal under CWE-40: Path Traversal: '\\UNC\share\name\' (Windows UNC Share).
Which Solr parent versions are affected?
Affected versions include releases prior to 8.11.1 across affected packages: org.apache.solr:solr-parent.
What version fixes CVE-2021-44548?
Upgrading to 8.11.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is solr-parent affected?
Yes, org.apache.solr:solr-parent is affected in releases prior to 8.11.1. Upgrade your dependency to 8.11.1 or later.
What is the CVSS score of CVE-2021-44548?
CVE-2021-44548 has a CVSS v3.1 base score of 9.8 (CRITICAL) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2021-44548?
CVE-2021-44548 is classified under CWE-40: Path Traversal: '\\UNC\share\name\' (Windows UNC Share) (The product accepts input that identifies a Windows UNC share ('\\UNC\share\name') that potentially redirects access to an unintended location or arbitrary file.).
How can I check Maven dependencies for CVE-2021-44548?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=org.apache.solr'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-pccr-q7v9-5f27",
  "modified" : "2022-08-11T18:41:45Z",
  "published" : "2022-01-06T21:32:35Z",
  "aliases" : [ "CVE-2021-44548" ],
  "summary" : "Apache Solr Improper Input Validation and Path Traversal",
  "details" : "An Improper Input Validation vulnerability in DataImportHandler of Apache Solr allows an attacker to provide a Windows UNC path resulting in an SMB network call being made from the Solr host to another host on the network. If the attacker has wider access to the network, this may lead to SMB attacks, which may result in: * The exfiltration of sensitive data such as OS user hashes (NTLM/LM hashes), * In case of misconfigured systems, SMB Relay Attacks which can lead to user impersonation on SMB Shares or, in a worse-case scenario, Remote Code Execution This issue affects all Apache Solr versions prior to 8.11.1. This issue only affects Windows.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "org.apache.solr:solr-parent"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "8.11.1"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-44548"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/apache/solr"
  }, {
    "type" : "WEB",
    "url" : "https://security.netapp.com/advisory/ntap-20220114-0005"
  }, {
    "type" : "WEB",
    "url" : "https://solr.apache.org/security.html#cve-2021-44548-apache-solr-information-disclosure-vulnerability-through-dataimporthandler"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20", "CWE-22", "CWE-40" ],
    "severity" : "CRITICAL",
    "github_reviewed" : true,
    "github_reviewed_at" : "2022-01-05T17:54:06Z",
    "nvd_published_at" : "2021-12-23T09:15:00Z"
  }
}