#VU86635 Arbitrary file upload in Apache Solr - CVE-2023-50386

Vulnerability identifier: #VU86635

Vulnerability risk: Medium

CVSSv4.0: 7.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Green]

CVE-ID: CVE-2023-50386

CWE-ID: CWE-434

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Apache Solr
Client/Desktop applications / Other client software

Vendor: Apache Foundation

Description

The vulnerability allows a remote user to compromise vulnerable system.

The vulnerability exists due to Solr ConfigSets accepts Java ".jar" and ".class" files to be uploaded through the ConfigSets API. Such files can be later included into a backup and executed during the restore procedure. When backing up Solr Collections, these configSet files would be saved to disk when using the LocalFileSystemRepository (the default for backups). If the backup was saved to a directory that Solr uses in its ClassPath/ClassLoaders, then the jar and class files would be available to use with any ConfigSet, trusted or untrusted. As a result, a remote user with backup permissions can include malicious files into the backup and execute arbitrary code on the system, when files are restored from the backup.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apache Solr: 6.0 - 6.0.1, 6.1 - 6.1.3, 6.2 - 6.2.1, 6.3 - 6.3.0, 6.4 - 6.4.2, 6.5 - 6.5.1, 6.6 - 6.6.6, 7.0.0 - 7.0.1, 7.1 - 7.1.0, 7.2 - 7.2.1, 7.3.0 - 7.3.1, 7.4.0, 7.5.0, 7.6.0, 7.7.0 - 7.7.3, 8.0.0, 8.1.0 - 8.11.1, 8.2.0, 8.3.0 - 8.3.1, 8.4.0 - 8.4.1, 8.5.0 - 8.5.2, 8.6.0 - 8.6.3, 8.7.0, 8.8.0 - 8.8.2, 8.9.0, 9.0.0, 9.1.0 - 9.1.1, 9.2.0 - 9.2.1, 9.3.0, 9.4.0

---

External links
https://lists.apache.org/thread/x4loddrb08dvkyp4c980w0yybklzof36

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, a fully functional exploit for this vulnerability is available.