Why SQL's = NULL Always Returns Zero Rows and How to Fix It

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Data analyst Michael Nocito published a tutorial on DEV Community on August 7, 2026, explaining one of the most common sources of confusion in SQL: using = NULL in queries. In SQL, NULL represents an unknown value rather than zero or empty text, so any comparison involving NULL yields an unknown result rather than true or false. Because the WHERE clause only passes rows where the condition evaluates to true, rows with NULL values are silently discarded alongside rows that evaluate to false. To correctly filter for missing values, developers should use IS NULL or IS NOT NULL instead of equality operators. Nocito demonstrates these concepts using a 10-row sample table containing intentionally seeded NULL values, with all queries verified in SQLite.

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New Windows RATs E4del and PINHOLE Hide Commands Inside FTP Server Banners

Security researchers at SOCRadar Threat Research Unit have identified two new Windows remote access trojans, E4del and PINHOLE, that use an unusual technique of embedding PowerShell commands inside FTP server pre-login banners to initiate infection. Victims are compromised when they open an LNK shortcut file inside a ZIP archive, which silently connects to an attacker-controlled FTP server and retrieves the hidden commands. E4del disguises itself as a Discord application using a signed Electron wrapper, offering capabilities including remote shell access, screen capture, and live streaming via WebSockets. PINHOLE employs a multi-stage loader that resolves encrypted command-and-control server details stored on legitimate platforms like Pinterest and SurveyMonkey, then proxies traffic through Cloudflare Workers before injecting the final payload into a suspended ApplicationFrameHost.exe process. Security teams are advised to block ZIP and LNK files at gateways, restrict outbound FTP traffic, and monitor for abnormal connections to Pinterest, SurveyMonkey, and Cloudflare Workers domains.

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ProgrammingDEV Community ·

Head Mare APT Exploits TrueConf Server Flaws to Spread PhantomCore Malware

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ProgrammingDEV Community ·

How to Design a Scalable URL Shortener System Like Bit.ly

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ProgrammingDEV Community ·

Google Warns Three Russia-Linked Groups Exploit Legitimate Auth Flows to Spy

Google Threat Intelligence Group published a report on August 20, 2026, detailing three Russia-linked threat clusters — UNC6293, UNC7005, and UNC5976 — abusing legitimate authentication mechanisms to compromise targeted individuals. Rather than relying solely on fake login pages, the attackers manipulate victims into completing real actions such as creating app passwords, approving OAuth logins, or linking WhatsApp devices, then capturing the resulting credentials or tokens. In some cases, targets are lured to sites mimicking secure call or file-sharing tools, where malware like VIDAR, ATOMIC, and HEADRUSH is also deployed to steal credentials, cookies, and audio-video data. The campaigns frequently involve impersonation of diplomats or trusted contacts to make the requests appear legitimate, with post-compromise access routed through residential proxies to evade detection. Google recommends blocking app passwords, enabling advanced phishing-resistant MFA, auditing linked devices, and verifying unexpected authentication requests through independent channels.

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