CVE-2026-96656

Plex Media Server arbitrary file write

CVSS 4.0 High 8.6Known exploited (CISA KEV)

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Description

Plex Media Server before 1.43.3.10861 allows an admin user to write arbitrary files that may be executed on load. The preference TranscoderH264Options is appended verbatim to x264's option string on every transcode. At startup, all .so files are run without signature, execute bit, or symbol checks.

Key data

CVSS 4.0 High 8.6

Score published by cisa-cg in the CVE record.

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Attack vector: Network
The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity: Low
No measurable action is needed to get around the system's built-in security controls. The attack is repeatable.
Attack requirements: None
The attack works without any special deployment or execution conditions.
Privileges required: High
An account with significant privileges, such as an administrator, is needed.
User interaction: None
No action from any user is needed.
Vulnerable system: confidentiality: High
Serious or total effect on the secrecy of data.
Vulnerable system: integrity: High
Serious or total effect on the trustworthiness of data.
Vulnerable system: availability: High
Serious or total effect on availability.
Subsequent systems: confidentiality: None
No effect on other systems' data secrecy.
Subsequent systems: integrity: None
No effect on other systems' data trustworthiness.
Subsequent systems: availability: None
No effect on other systems' availability.

Metric	Value	What it means
Attack vector	Network	The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity	Low	No measurable action is needed to get around the system's built-in security controls. The attack is repeatable.
Attack requirements	None	The attack works without any special deployment or execution conditions.
Privileges required	High	An account with significant privileges, such as an administrator, is needed.
User interaction	None	No action from any user is needed.
Vulnerable system: confidentiality	High	Serious or total effect on the secrecy of data.
Vulnerable system: integrity	High	Serious or total effect on the trustworthiness of data.
Vulnerable system: availability	High	Serious or total effect on availability.
Subsequent systems: confidentiality	None	No effect on other systems' data secrecy.
Subsequent systems: integrity	None	No effect on other systems' data trustworthiness.
Subsequent systems: availability	None	No effect on other systems' availability.

CVSS 3.1 High 7.2

Score published by cisa-cg in the CVE record.

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Attack vector: Network
The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity: Low
No special conditions are needed. The attack can be repeated at will.
Privileges required: High
An account with significant privileges, such as an administrator, is needed.
User interaction: None
No action from any user is needed.
Scope: Unchanged
The impact stays within the vulnerable component.
Confidentiality impact: High
Serious or total effect on the secrecy of data.
Integrity impact: High
Serious or total effect on the trustworthiness of data.
Availability impact: High
Serious or total effect on availability.

Metric	Value	What it means
Attack vector	Network	The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity	Low	No special conditions are needed. The attack can be repeated at will.
Privileges required	High	An account with significant privileges, such as an administrator, is needed.
User interaction	None	No action from any user is needed.
Scope	Unchanged	The impact stays within the vulnerable component.
Confidentiality impact	High	Serious or total effect on the secrecy of data.
Integrity impact	High	Serious or total effect on the trustworthiness of data.
Availability impact	High	Serious or total effect on availability.

CVSS is owned and managed by FIRST.Org, Inc. (FIRST) and is used by permission. Each CVSS score on this site is shown together with its vector string, as published in the CVE record by the source named next to it. Learn more at first.org/cvss.

EPSS

Exploit Prediction Scoring System by FIRST: an estimate of the probability that exploitation activity will be observed in the next 30 days.

Score: 0.01785 (1.8% probability)
Percentile: 78.5%
Scores of: Nov 10, 2026
Model: v2026.06.15

CISA Known Exploited Vulnerabilities

This CVE is listed in the CISA KEV catalog.

Name in the catalog: Plex Media Server External Control of File Name or Path Vulnerability
Added to the catalog: Oct 20, 2026
Federal due date: Oct 23, 2026

CISA assessment as of Oct 19, 2026

Stakeholder-Specific Vulnerability Categorization (SSVC) decision points added by CISA.

Exploitation: Recorded by CISA as active
Automatable: no
Technical impact: total

Weakness (CWE)

CWE catalog version 5.0.

CWE-73External Control of File Name or Path

Affected products

Products listed in the CVE record, as the CNA published them.

Plex Media Server
- affected: before 1.43.3.10861
- unaffected: 1.43.3.10861

References

Links listed in the CVE record. They lead to other sites, which CubePath does not control.

url (forums.plex.tv)release-notes
url (cve.org)vdb-entry
url (raw.githubusercontent.com)third-party-advisory
url (zmain.info)third-party-advisory

Timeline

ID reservedSep 23, 2026
Record publishedSep 23, 2026
Added to CISA KEVOct 20, 2026
Record last updatedOct 21, 2026

Look up another CVE

About CubePath

CubePath is a cloud provider with data centers in Europe and the United States. It offers VPS, bare metal servers and DDoS protection.

Cloud VPS DDoS protection

Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:05 UTC. Sources and licenses