Category

Buffer Overflow

Security vulnerabilities and automated fixes for buffer overflow issues

251 posts found

Buffer overflow vulnerabilities occur when a program writes data beyond the boundaries of allocated memory, allowing attackers to overwrite adjacent memory and potentially execute arbitrary code. These flaws are among the most dangerous in systems programming and have been responsible for countless critical exploits.

Related CWEs

CWE-120CWE-121CWE-122CWE-787CWE-125

Affected Languages

CC++Rust (unsafe)Assembly
critical9 min

How Buffer Overflow via strcpy() Happens in C++ XML Parsers and How to Fix It

A critical buffer overflow vulnerability was discovered in `buildroot-external/package/libxmlparser/xmlParser.cpp`, where the `toXMLString` function used `_tcscpy()` to write XML escape sequences into a destination buffer without any bounds checking. An attacker supplying a crafted XML document could overflow the buffer and potentially execute arbitrary code. The fix replaces all five unsafe `_tcscpy()` calls with `memcpy()` calls that copy only the exact number of bytes required for each escape

#buffer-overflow#cpp#xml-parsing+2 more
A
anupamme
Aug 26, 2026
high8 min

How insecure string copy functions happen in C and how to fix it

A high-severity buffer overflow vulnerability was discovered in `tools/claude-vscode-wrapper.c`, where an unbounded `strcpy()` call copied a file path into a fixed-size `MAX_PATH` buffer without any size validation. The fix replaces `strcpy()` with `snprintf()` and swaps `malloc()` for `calloc()`, ensuring both string operations and memory allocation are bounds-safe and zero-initialized.

#buffer-overflow#c#memory-safety+3 more
A
anupamme
Aug 26, 2026
critical9 min

How Heap Buffer Overflows Happen in C++ ZIP Extraction and How to Fix Them

A critical heap buffer overflow vulnerability was discovered in `TKLiveSync/unzip.cpp`, where ZIP archive entry names were copied into a `PATH_MAX`-sized heap buffer using `strcpy()` without any length validation. Since the ZIP specification allows entry names up to 65,535 bytes — far exceeding typical `PATH_MAX` values of 1,024 to 4,096 bytes — a crafted archive could overflow the buffer and corrupt heap memory. The fix replaces the unsafe `strcpy`/`dirname` pattern with `std::string` operation

#buffer-overflow#cpp#memory-safety+2 more
A
anupamme
Aug 26, 2026
medium8 min

How Integer Overflow happens in C++ image processing and how to fix it

A signed integer overflow in OpenCV's `bilateralFilter.cpp` allowed the buffer size calculation `cal_width * cal_height * cn` to wrap around to a small or negative value, causing `padding.resize()` to allocate far less memory than needed. Subsequent `memcpy` operations would then write beyond the allocated buffer, creating a heap corruption primitive. The fix is a single targeted cast to `size_t` that promotes the multiplication to unsigned 64-bit arithmetic before any overflow can occur.

#buffer-overflow#integer-overflow#cpp+4 more
A
anupamme
Aug 26, 2026
critical7 min

How Stack Buffer Overflows Happen in C with sprintf() and How to Fix Them

A critical stack buffer overflow was discovered in `libuv/Learn-libuv/docs/code/tty-gravity/main.c` where `sprintf()` wrote ANSI escape sequences and user-controlled variables into a fixed 500-byte buffer without any bounds checking. An attacker controlling the `pos`, `width`, or `message` variables could overflow the stack, overwrite return addresses, and potentially achieve arbitrary code execution. The fix replaces `sprintf()` with `snprintf()` and adds explicit length validation to ensure wr

#buffer-overflow#c#memory-safety+3 more
A
anupamme
Aug 26, 2026
high7 min

How insecure string copy functions happen in C and how to fix them

A high-severity buffer overflow risk was discovered in `login/main.c` where `strcpy()` was used to copy the `HOME` environment variable into a fixed-size 512-byte buffer without any bounds checking. An attacker controlling the `HOME` environment variable could overflow `pwd_file_name`, potentially corrupting memory or hijacking execution. The fix replaces the two-step `strcpy`/`strcat` pattern with a single, bounds-safe `snprintf` call.

#c#buffer-overflow#strcpy+4 more
A
anupamme
Aug 22, 2026
critical9 min

How buffer overflow in Intel SGX enclave ECALLs happens in C and how to fix it

A critical buffer overflow vulnerability was discovered in Intel SGX enclave functions `ecall_encrypt_data` and `ecall_decrypt_data` in `backend/sgx/enclave/enclave.c`. The functions performed memory operations without validating that the provided buffer lengths matched the actual allocated buffer sizes, allowing an attacker controlling the untrusted application to trigger heap corruption within the secure enclave by passing oversized length parameters.

#security#buffer-overflow#intel-sgx+4 more
A
anupamme
Jul 27, 2026
critical8 min

How buffer overflow happens in C SGX enclave memcpy and how to fix it

A critical buffer overflow vulnerability was discovered in `backend/sgx/enclave/enclave.c` where the `ecall_store_data` function performed `memcpy` operations without proper bounds checking against the actual destination buffer size. An attacker could supply a malicious `data_len` parameter to overflow the enclave's secure storage buffer, potentially corrupting trusted execution environment memory. The fix replaces a hardcoded magic number check with a precise size comparison against the actual

#buffer-overflow#c#sgx+4 more
A
anupamme
Jul 26, 2026
medium7 min

How integer underflow in array splice operations happens in C and how to fix it

A critical integer underflow vulnerability was discovered in tree-sitter's array.h header file, where the `_array__splice()` function calculated array sizes without proper bounds checking. The vulnerable code relied on assert() statements that are disabled in release builds, allowing arithmetic underflow when `old_count > *size + new_count`, potentially causing memory corruption through out-of-bounds memcpy operations.

#c#integer-underflow#buffer-overflow+4 more
A
anupamme
Jul 25, 2026
high6 min

How buffer overflow via sprintf() happens in C string formatting and how to fix it

A high-severity buffer overflow vulnerability was discovered in `bench/strbuild/strbuild.c` where `sprintf()` wrote formatted output into a 64-byte stack buffer (`line[64]`) without any bounds checking. An attacker who could influence the values in the `NAMES[]`, `c[]`, or `v[]` arrays could overflow this buffer, potentially corrupting the stack and hijacking control flow. The fix replaces `sprintf()` with `snprintf(line, sizeof(line), ...)` to enforce a strict 64-byte write limit.

#security#buffer-overflow#c+4 more
A
anupamme
Jul 23, 2026
critical7 min

How buffer overflow happens in C tar header parsing and how to fix it

A critical buffer overflow vulnerability was discovered in `microtar/microtar.c` where the `raw_to_header()` and `header_to_raw()` functions used unbounded `strcpy()` and `sprintf()` calls to copy tar header fields. Malicious tar files with non-null-terminated name fields could overflow destination buffers, potentially leading to code execution. The fix replaces all unsafe string operations with bounded alternatives: `memcpy()` with explicit null-termination and `snprintf()` instead of `sprintf(

#buffer-overflow#c-security#tar-parsing+4 more
O
orbisai0security
Jul 13, 2026
critical8 min

How buffer overflow happens in C ieee80211_input() and how to fix it

A critical buffer overflow vulnerability was discovered in `src/firmware/src/net/ieee80211.c` at line 1584, where the `ieee80211_input()` function processed raw 802.11 data frames without verifying that the incoming frame was large enough to contain a valid `ieee80211_frame` header. An attacker within wireless range could craft undersized or malformed frames to trigger memory corruption, potentially leading to remote code execution on the firmware. The fix adds a single, targeted bounds check th

#buffer-overflow#c#firmware+4 more
O
orbisai0security
Jul 13, 2026