Internxt is a post-quantum secure encrypted cloud storage provider which is open-source and has passed multiple independent audits.

I reviewed their code and found that post-quantum security should have been the least of their problems. Clicking a link in your browser could trigger remote code execution on the desktop app or leak your long-term encryption keys to an attacker-chosen URL. Their cryptographic architecture stands on shaky grounds with public keys never being verified, in some cases man-in-the-middled by design, a flat key hierarchy and a KDF with just 3 iterations of MD5.

We need PQC and we need it now, but adding a (self-rolled) PQC hybrid on top of a weak protocol does not make it more secure.

When analysing firmware attack surfaces, image decoders built into bootloaders get less scrutiny than cryptographically verified OS kernels. If image parsing happens before signature verification, any memory corruption in the parser breaks the secure boot trust model.

researchers analysed U-Boot's video subsystem (drivers/video/video_bmp.c) and identified an unbounded write in the RLE8 bitmap decoder (video_display_rle8_bitmap()) that leads to a pre-authentication Secure Boot bypass.

Root Cause and Vulnerability Mechanics

When U-Boot displays a boot logo or splash screen, it parses a BMP image loaded from local storage (SPI flash, MMC/eMMC, USB, or SD card).

Unbounded framebuffer write: During RLE8 decompression, video_display_rle8_bitmap() decodes run-length encoded streams directly into the active framebuffer without validating stream bounds against the frame boundary or allocated buffer size.

Pre-authentication execution window: In many embedded target configurations, the boot splash screen is rendered immediately on startup, before U-Boot calls Android Verified Boot (AVB) or FIT image signature verification routines.

Storage disparity: The kernel image and rootfs are signed, but splash images are frequently stored in unsigned, user-writable partitions or external media.

An attacker who writes a crafted RLE8 BMP to the boot storage can trigger an out-of-bounds write past the framebuffer during early boot, corrupting adjacent bootloader data structures, function pointers, or verification flags in memory.

This hijacks the execution flow before signature checking completes.

TL;DR. SConnect - 1M+ users, an extension middleware+native host for authentication with eIDs, 3SKeys and other hardware signing tokens had a drive-by RCE which enabled any site or iframe a user saw to silently download and execute a dll due to a poor hand-rolled implementation of RSA-2048 token validation, enabling a use of uninitialized memory validation bypass which enabled "plugins" (DLLs) to be loaded. v2.16.0.0 of the extension and native host is vulnerable. CVE-2026-18397. CVSS 9.4.

API Connections allow anyone to fully compromise any other connection worldwide, giving full access to the connected backend.

A blue-team writeup on detecting a compromised MikroTik from its own config. Seven techniques, each with the collection command, the artifact it leaves behind, and a triage step. Feedback welcome.

Questions regarding netsec and discussion related directly to netsec are welcome here, as is sharing tool links.

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