CVE-2021-35394
Published: 16 August 2021
Summary
CVE-2021-35394 is a critical-severity OS Command Injection (CWE-78) vulnerability in Realtek Rtl819X Jungle Software Development Kit. Its CVSS base score is 9.8 (Critical).
Operationally, ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and SI-10 (Information Input Validation).
Deeper analysis
Realtek Jungle SDK versions v2.x through v3.4.14B include a diagnostic component known as MP Daemon, typically built as the UDPServer binary, that contains multiple memory corruption issues along with an arbitrary command injection flaw tracked under CWE-78. The affected SDK is widely used in networking and IoT devices, and the vulnerabilities received a CVSS v3.1 score of 9.8.
Remote unauthenticated attackers can exploit the flaws over the network without any user interaction or credentials. Successful exploitation grants full control of the confidentiality, integrity, and availability of the device, enabling arbitrary command execution and potential memory corruption attacks that can lead to crashes or further code execution.
Public advisories referenced in the CVE entry, including reports from IoT Inspector and a security bulletin from Realtek, document the issues and point to vendor guidance for affected SDK versions. No information on observed in-the-wild exploitation is supplied in the source data.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-22037
Vulnerability details
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…
more
exploited by remote unauthenticated attackers.
- CWE(s)
- KEV Date Added
- 10 December 2021
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly enforces input validation and sanitization to block the arbitrary command injection (CWE-78) and memory corruption flaws in the exposed UDPServer binary.
Enforces access control so the diagnostic MP Daemon cannot be reached by remote unauthenticated attackers over the network.
Applies memory protection mechanisms that mitigate exploitation of the memory corruption vulnerabilities present in the SDK binary.