A Deep Dive Into Attempted Exploitation of CVE-2023
Mirai-like botnet scans exploit TP-Link EOL router flaw CVE-2023-33538 after CISA KEV addition, though observed exploit code is flawed.
Unit 42 observed large-scale automated scans attempting to exploit CVE-2023-33538 in end-of-life TP-Link TL-WR940N, TL-WR740N and TL-WR841N routers after CISA added the flaw to its KEV catalog in June 2025. HTTP GET requests inject commands via the ssid1 parameter at the /userRpm/WlanNetworkRpm endpoint to download and execute an arm7 ELF binary, a Mirai variant related to the Condi IoT botnet. Firmware emulation and reverse engineering showed the observed exploits are flawed and would fail, but the underlying vulnerability is real and successful exploitation requires authentication to the router's web interface. TP-Link confirmed the devices are end-of-life with no patches available and recommends replacing units and eliminating default credentials.
ThreatsDay: 296K IoT Botnet, 100+ Water Systems Targeted, SharePoint RCE Chain + 27 New Stories
Weekly ThreatsDay bulletin details a ShinyHunters-style social engineering hit on ReliaQuest, the 296,000-device Dysphoria IoT botnet, and several new malware families.
ReliaQuest confirmed a social engineering attack on August 22, 2026, in which an attacker used a fake SSO page and MFA push approval to gain brief view-only access to an identity dashboard, with tactics matching ShinyHunters, which has since listed the firm on its leak portal. The Shadowserver Foundation reported the Dysphoria botnet has compromised nearly 296,000 IoT devices for DDoS attacks and recently added residential proxy capability. Cisco Talos documented JWR, an operator-driven phishing-as-a-service framework linked to The Outsider that harvests credentials, identity documents, and 2FA codes over an encrypted WebSocket. New malware coverage includes the Octagon Android fraud bot ($1,400/month), the C2Looper Rust backdoor delivered via ClickFix, and the Aeternum loader that moved C2 to the Polygon blockchain.