Buffer Manipulation Vulnerability in LibreDWG Library Affecting Multiple Applications

CVE-2026-54610

What is CVE-2026-54610?

The LibreDWG Library, a free C library for reading and writing DWG files, contains a vulnerability in the bit_TV_to_utf8() function located in src/bits.c prior to version 0.14. This function improperly handles input that is marked as const, allowing it to overwrite the caller's buffer in certain situations. If an iconv() error occurs that is not E2BIG, the function incorrectly frees the output buffer and processes the original input buffer via bit_u_expand(). This can lead to significant issues, including segmentation faults when dealing with immutable buffers like string literals or read-only mappings, potentially resulting in a Denial of Service. If mutable buffers are used, they can be altered unexpectedly, posing serious security risks, especially in applications that allow untrusted input through the conversion API.

References