CVE-2021-35394
Realtek Jungle SDK version v2.x up to v3.4.14B provides a diagnostic tool called 'MP Daemon' that is usually compiled as 'UDPServer' binary. The…
Browse: All 2021 CVEs · All vendors
- CVSS score
- 9.8 Critical
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H- CISA KEV
- Yes — actively exploited (added 2021-12-10, remediation due 2021-12-24)
- Weakness (CWE)
- NVD-CWE-Other, CWE-78
- Published
- 2021-08-16
- Last modified
- 2026-06-17
- NVD status
- Analyzed
Description
Realtek Jungle SDK version v2.x up to v3.4.14B provides a diagnostic tool called 'MP Daemon' that is usually compiled as 'UDPServer' binary. The binary is affected by multiple memory corruption vulnerabilities and an arbitrary command injection vulnerability that can be exploited by remote unauthenticated attackers.
Affected products
- realtek rtl819x jungle software development kit
Affected ranges per NVD CPE data; confirm exact versions in the vendor advisory.
Required action (CISA)
Apply updates per vendor instructions. Federal remediation deadline: 2021-12-24.
How to prioritize this
This vulnerability is on the CISA KEV list, meaning it is being actively exploited — treat it as urgent regardless of the raw CVSS number. Use the live CVE lookup for the latest NVD data, and the CVSS 3.1 calculator to model your own environmental score. For the actively exploited vulnerabilities that matter this week, read The Exploit HQ daily security brief.
References
- https://www.iot-inspector.com/blog/advisory-multiple-issues-realtek-sdk-iot-supply-chain
- https://www.realtek.com/en/cu-1-en/cu-1-taiwan-en
- https://www.realtek.com/images/safe-report/Realtek_APRouter_SDK_Advisory-CVE-2021-35392_35395.pdf
- https://www.securityfocus.com/archive/1/534765
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-35394
FAQ
Is CVE-2021-35394 actively exploited?
Yes. CISA added CVE-2021-35394 to its Known Exploited Vulnerabilities (KEV) catalog on 2021-12-10, with a federal remediation deadline of 2021-12-24. A KEV listing means real-world exploitation is confirmed, so patching this should be prioritized above many higher-CVSS bugs that aren't being exploited.
What is the CVSS score of CVE-2021-35394?
CVE-2021-35394 has a CVSS base score of 9.8 (Critical). Its vector string is CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.
Related vulnerabilities
- CVE-2014-8361 — Realtek SDK
- CVE-2021-35395 — Realtek AP-Router SDK
- CVE-2025-39682 — Linux Kernel
- CVE-2012-1854 — Microsoft Visual Basic for Applications (V
- CVE-2023-0386 — Linux Kernel
- CVE-2025-35939 — Craft CMS Craft CMS
Data source: NVD & CISA KEV. Shown as-is; nothing added. Last generated from NVD data — re-check the live tool for updates.
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