CVE-2026-96655: Plex Media Server Server-Side Request Forgery (SSRF) Vulnerability

Should you act?

Exploited: patch now if you run it

CISA has confirmed exploitation in the wild. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Yes, if you run Plex Media Server. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2026-10-20, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-11-03; treat that as the outer limit, not the target.
• EPSS 0.4%, percentile 35: FIRST’s model estimates a 0.4% chance of exploitation activity in the next 30 days, higher than 35% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Needs an account (low (any account)). Exposure depends on who can log in.
• Editorial verdict: Act now. Plex2Shell: Exploited RCE Chain in Plex Media Server — A public proof of concept chains four Plex bugs into code execution without credentials, and attackers have used it since October 17: update any internet-reachable server now, then check it for a miner or proxy.

What it is

Plex Media Server before 1.43.3.10861 allows an authenticated user to request arbitrary internal or external addresses via the '/video/:/transcode/universal' path parameter.

CISA’s summary

Plex Media Server contains a server-side request forgery (SSRF) vulnerability that could allow an authenticated user to request arbitrary internal or external addresses via the '/video/:/transcode/universal' path parameter. This vulnerability can be chained with CVE-2026-96652, CVE-2026-96654, and CVE-2026-96656.

Weakness type: CWE-918.

Product: Plex Media Server · Assigned by: cisa-cg · Published: 2026-09-23

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Attack requirements: none
• Privileges required: low (any account)
• User interaction: none

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: added 2026-10-20; federal due date 2026-11-03. Known ransomware use: Unknown.
• CISA required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
• CISA SSVC assessment: exploitation active, automatable no, technical impact partial.
• FIRST EPSS (model of 2026-10-21): 0.42% probability of exploitation activity in the next 30 days; percentile 35.

Timeline

• 2026-09-23 — CVE record published by cisa-cg
• 2026-10-20 — Added to CISA’s Known Exploited Vulnerabilities catalog
• 2026-10-20 — erroneo.us brief: Plex2Shell: Exploited RCE Chain in Plex Media Server
• 2026-10-21 — CVE record last updated
• 2026-11-03 — CISA remediation deadline for US federal agencies

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vendor and project advisories, patches

1. url forums.plex.tv
2. Listed in CISA KEV notes (forums.plex.tv) forums.plex.tv

Vulnerability records

1. CVE.org record CVE-2026-96655 cve.org
2. NVD entry CVE-2026-96655 nvd.nist.gov

Government

1. CISA Known Exploited Vulnerabilities catalog entry cisa.gov
2. Listed in CISA KEV notes (cisa.gov) cisa.gov
3. Listed in CISA KEV notes (cisa.gov) cisa.gov

Other references from the CVE record and advisory

1. url raw.githubusercontent.com
2. url zmain.info

All exploited Plex vulnerabilities · Today’s Security Digest