CVE-2021-44548

Apache Solr information disclosure vulnerability through DataImportHandler

Description

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.

Remediation

Workaround:

  • Upgrade to Solr 8.11.1, and/or ensure only trusted clients can make requests to Solr's DataImport handler.

Categories

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.13% Top 25%
Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Solr
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-44548?
CVE-2021-44548 has been scored as a critical severity vulnerability.
How to fix CVE-2021-44548?
As a workaround for remediating CVE-2021-44548: Upgrade to Solr 8.11.1, and/or ensure only trusted clients can make requests to Solr's DataImport handler.
Is CVE-2021-44548 being actively exploited in the wild?
It is possible that CVE-2021-44548 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-44548?
CVE-2021-44548 affects Apache Software Foundation Apache Solr.
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