Category

Firmware Security

Security vulnerabilities and automated fixes for firmware security issues

11 posts found

high6 min

How integer truncation heap overflow happens in C++ UEFI ACPI parsing and how to fix it

A high-severity integer truncation vulnerability was discovered in `Mobility.Uefi.Acpi.cpp` where heap allocation sizes were stored in a 16-bit integer (`MO_UINT16`), causing silent truncation when the computed size exceeded 65535 bytes. This led to undersized heap allocations followed by out-of-bounds writes, exploitable by an attacker who can influence ACPI SRAT table contents in virtualized environments. The fix promotes the size variable to `MO_UINTN` (platform-native width) to prevent trunc

#security#buffer-overflow#integer-overflow+4 more
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orbisai0security
Jul 10, 2026
critical7 min

How buffer overflow happens in C sprintf() calls and how to fix it

A critical stack buffer overflow vulnerability was discovered in `IxNpeMicrocode.h`, where unbounded `sprintf()` calls wrote attacker-controlled data into fixed-size stack buffers without any length limit. By replacing `sprintf()` with `snprintf()` and passing the destination buffer sizes, the firmware loading tool is now protected against crafted NPE microcode blobs that could trigger arbitrary code execution. This is a textbook example of how a single unsafe C function call can open the door t

#buffer-overflow#c#sprintf+4 more
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orbisai0security
Jul 9, 2026
critical8 min

How buffer overflow in rcdevice.c request parser happens in C and how to fix it

A critical buffer overflow vulnerability was discovered in `src/main/io/rcdevice.c` at line 489, where the RC device request parser wrote incoming data into a fixed-size buffer without validating against the hard-coded maximum capacity `RCDEVICE_PROTOCOL_MAX_DATA_SIZE`. An attacker controlling the device's I/O data stream could overflow the buffer by sending a payload longer than `expectedDataLength`, potentially achieving arbitrary code execution. The fix adds a second bounds check against the

#buffer-overflow#c#embedded+4 more
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orbisai0security
Jul 6, 2026
critical8 min

How buffer overflow happens in C TinyGSM sprintf and how to fix it

A critical buffer overflow vulnerability was discovered in `TinyGsmClientSequansMonarch.h` at line 515, where `sprintf` was writing a two-character hex string into a buffer only two bytes large — leaving no room for the null terminator. The fix replaces `sprintf` with `snprintf` and increases the buffer to three bytes, preventing a one-byte overflow that could corrupt adjacent memory in embedded firmware.

#buffer-overflow#c-cpp#embedded-security+5 more
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orbisai0security
Jul 5, 2026
high7 min

How buffer overflow via strcpy() happens in Nordic BLE C firmware and how to fix it

A high-severity buffer overflow vulnerability was discovered in the Nordic BLE Central Demo firmware, where unsafe `strcpy()` and `sprintf()` calls in the `BleDevDiscovered()` function could allow attackers to overflow stack buffers by sending specially crafted BLE service discovery responses. The fix replaced all unbounded string operations with size-checked `snprintf()` calls, preventing potential remote code execution in embedded Bluetooth devices.

#buffer-overflow#embedded-security#bluetooth+4 more
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orbisai0security
Jun 27, 2026
critical9 min

How heap buffer overflow happens in C WiFi frame capture and how to fix it

A critical buffer overflow vulnerability in the ESP32 WiFi frame capture feature (feat_capture_hs.c) allowed attackers within WiFi range to craft oversized 802.11 frames that would overflow heap buffers and achieve remote code execution. The fix adds explicit length validation before memcpy operations and rejects oversized frames rather than silently truncating them.

#buffer-overflow#c-security#embedded-systems+4 more
O
orbisai0security
Jun 15, 2026
medium8 min

Integer Overflow in Shared Memory Bounds Check: How a Missing Cast Opened the Door to Arbitrary Memory Writes

A subtle but dangerous integer overflow vulnerability was discovered in `lib/rpmi_shmem.c`, where bounds checks on shared memory operations could be silently bypassed due to 32-bit arithmetic overflow. By carefully crafting `offset` and `len` values, an OS-level or hypervisor-level caller could direct firmware writes to arbitrary memory addresses — including interrupt vector tables and security-critical configuration structures. The fix was elegantly simple: casting operands to 64-bit before add

#integer-overflow#firmware-security#memory-safety+4 more
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orbisai0security
May 28, 2026
critical7 min

Critical Buffer Overflow in RC Device Parser: How One Missing Bounds Check Opens the Door to Memory Corruption

A critical buffer overflow vulnerability was discovered in the RC device request parser (`rcdevice.c`), where incoming packet data was written to a fixed-size buffer using an attacker-controlled length field as the only guard. Because the expected data length was parsed directly from the packet without being validated against the actual allocated buffer size, a malicious packet could overflow the buffer and overwrite adjacent stack or heap memory with arbitrary bytes. The fix adds a single, esse

#buffer-overflow#embedded-security#c-programming+4 more
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orbisai0security
May 28, 2026
high7 min

Buffer Overflow in RS-232 Serial Input: How a Missing Length Check Put Embedded Systems at Risk

A critical buffer overflow vulnerability was discovered in `serial.c`, where the `rs232_buffered_input` function could write more bytes than the destination buffer `rs232_ibuff` could hold — with no size limit to stop it. An attacker with access to the RS-232 serial port could exploit this to overwrite adjacent OS memory, including return addresses and critical data structures. The fix adds a simple but essential bounds check that clamps the returned byte count to the actual buffer size.

#buffer-overflow#embedded-security#c-programming+4 more
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orbisai0security
May 28, 2026
medium7 min

Unauthenticated Firmware Upload: When Anyone Can Flash Your Network Switch

A critical vulnerability in an embedded HTTP server allowed any unauthenticated attacker to upload and flash arbitrary firmware images to a network switch — no credentials required. Because malicious firmware survives reboots and factory resets, a successful attack could permanently compromise an entire fleet of devices with backdoors or rootkits. The fix adds an authentication gate and corrects dangerous CRC-check logic that would reset the device even on a failed checksum.

#firmware-security#authentication#embedded-systems+4 more
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orbisai0security
May 28, 2026
critical9 min

Critical Heap Buffer Overflow in Firmware Audio Processing: How a Missing Bounds Check Could Let Attackers Take Control

A critical heap buffer overflow vulnerability was discovered and patched in firmware audio processing code, where a missing bounds validation before a `memcpy` operation could allow attackers to overflow a heap-allocated audio buffer and overwrite adjacent memory. This type of vulnerability is particularly dangerous in embedded firmware because it can lead to arbitrary code execution, system crashes, or complete device compromise. The fix adds proper bounds checking before the copy operation, en

#buffer-overflow#heap-overflow#firmware-security+4 more
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orbisai0security
May 13, 2026