CVE-2021-33959
Plex media server 1.21 and before is vulnerable to ddos reflection attack via plex service.
Plex media server 1.21 and before is vulnerable to ddos reflection attack via plex service.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
Plex media server 1.21 and before is vulnerable to ddos reflection attack via plex service.
- Record
CVE-2021-33959- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-346
- Updated
- 2026-11-02
CVE List
Plex media server 1.21 and before is vulnerable to ddos reflection attack via plex service.
- Record
CVE-2021-33959- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-346
- Updated
- 2026-11-02
EUVDEUVD-2021-20630
Plex media server 1.21 and before is vulnerable to ddos reflection attack via plex service.
- Record
EUVD-2021-20630- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-8788-3qj3-84j7
Plex media server 1.21 and before is vulnerable to ddos reflection attack via plex service.
Plex media server 1.21 and before is vulnerable to ddos reflection attack via plex service.
- Record
GHSA-8788-3qj3-84j7- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-346, CWE-400
- Updated
- 2026-11-02
Affected products
Public exploits
Links only. Every CVE stores no exploit code.
| Source | Link | Date |
|---|---|---|
| PoC in GitHub | lixiang957/CVE-2021-33959 | 2023-01-15 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, PoC in GitHub |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-33959 is a high vulnerability (CVSS 7.5) in Plex Media Server, published January 18, 2023. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 15.0%, the 96th percentile. No source names a fixed version.