CVE-2021-42835
7.0 · HIGHOverview
CVE-2021-42835 is a high-severity vulnerability affecting plex media_server. It was published on December 8, 2021 and has a CVSS 3.1 base score of 7.0 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.0, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical Description
An issue was discovered in Plex Media Server through 1.24.4.5081-e362dc1ee. An attacker (with a foothold in a endpoint via a low-privileged user account) can access the exposed RPC service of the update service component. This RPC functionality allows the attacker to interact with the RPC functionality and execute code from a path of his choice (local, or remote via SMB) because of a TOCTOU race condition. This code execution is in the context of the Plex update service (which runs as SYSTEM).
Remediation
Check the references section for vendor advisories and patches from plex. Update media_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| plex | media_server | >= 0, < 1.25.0.5282 | Affected |
References
Frequently Asked Questions
What is CVE-2021-42835?
CVE-2021-42835 is a high-severity vulnerability affecting plex media_server. It was published on December 8, 2021 and has a CVSS 3.1 base score of 7.0 (HIGH).
How severe is CVE-2021-42835?
This vulnerability has a CVSS 3.1 base score of 7.0, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2021-42835?
Check the references section for vendor advisories and patches from plex. Update media_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-42835?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-42835 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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