Talos Vulnerability Report TALOS-2023-1874 Realtek rtl819x Jungle SDK boa formUpload firmware update vulnerability July 8, 2024 CVE Number CVE-2023-34435 SUMMARY A firmware update vulnerability exists in the boa formUpload functionality of Realtek rtl819x Jungle SDK v3.4.11. A specially crafted network packets can lead to arbitrary firmware update. An attacker can provide a malicious file to trigger this vulnerability. CONFIRMED VULNERABLE VERSIONS The versions below were either tested or verified to be vulnerable by Talos or confirmed to be vulnerable by the vendor. LevelOne WBR-6013 RER4_A_v3411b_2T2R_LEV_09_170623 Realtek rtl819x Jungle SDK v3.4.11 PRODUCT URLS rtl819x Jungle SDK – https://www.realtek.com/en/ WBR-6013 – https://www.level1.com/level1_en/wbr-6013-n300-wireless-router-54069103 CVSSv3 SCORE 7.2 – CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H CWE CWE-347 – Improper Verification of Cryptographic Signature DETAILS The rtl819x Jungle SDK is an SDK for routers. This SDK uses as web server boa. This Realtek rtl819x Jungle SDK vulnerability was found while researching the Levelone WBR-6013 router. We are going to explain this vulnerability from the perspective of the WBR-6013 router. The WBR-6013 router has a web server called boa. This web server offers, through the /boafrm/formUpload, API functionality to upgrade the firmware with a newer one. The WBR-6013, throughout the whole firmware upgrade process, never checks the validity of the uploaded firmware. This…Read More