CVE-2021-42835

mediumpriority · track · 38EPSS 0.012 · 68 %ileexploit · PoCEUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

1 exploit · PoC

Likely / severe?

1.19% (68th) EPSS

CVSS 6.9 · medium

Is it mine?

2 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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).

cvss

Technical severity, 0–10. One row per scoring source.

7.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–7

v2.06.9mediumAV:L/AC:M/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 3.4 · impact 10

v3.17highCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 1 · impact 5.9

v3.16.6mediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Psecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-367USprimary

exploits (1)

Public proof-of-concept and weaponised exploit code.

netanelc305/PlEXcalaisonPlex media server local privilige escalation poc - CVE-2021-42835PoC · poc_in_github

affected products (2)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
plex media server< 1.25.0.5282nvdUScpe:2.3:a:plex:media_server:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-12-08modified 2026-06-17

related (1,061)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2025-38352US	—OT critical	1.36% (72nd)	KEV	2025-07-22
In the Linux kernel, the following vulnerability has been resolved: posix-cpu-timers: fix race between handle_posix_cpu_timers() and posix_cpu_timer_del() If an exiting non-autor…
CVE-2025-22224US	high8.2OT critical	1.56% (75th)	KEV	2025-03-04
VMware ESXi, and Workstation contain a TOCTOU (Time-of-Check Time-of-Use) vulnerability that leads to an out-of-bounds write. A malicious actor with local administrative privileges…
CVE-2024-30088US	—OT critical	68.2% (99th)	KEV	2024-06-11
Windows Kernel Elevation of Privilege Vulnerability
CVE-2022-48618US	high7.0OT critical	0.49% (42nd)	KEV	2024-01-09
The issue was addressed with improved checks. This issue is fixed in macOS Ventura 13.1, watchOS 9.2, iOS 16.2 and iPadOS 16.2, tvOS 16.2. An attacker with arbitrary read and write…
CVE-2023-35311US	—OT critical	15.5% (97th)	KEV	2023-07-11
Microsoft Outlook Security Feature Bypass Vulnerability

+1056 more

references (14)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan