A stack-based buffer overflow exists in the raw_to_header function in src/microtar.c for rxi microtar 0.1.0. The function copies the 100‑byte name and linkname fields of a TAR header with strcpy without guaranteeing null termination of the source. Because the source data may lack a terminating null byte, strcpy can read beyond the buffer boundary, resulting in an overflow on the stack that could corrupt adjacent data and lead to arbitrary code execution or a crash. The flaw is classified as CWE‑121 and CWE‑170.

The vulnerability affects all instances of rxi microtar version 0.1.0. No other affected versions are listed.

The CVSS score of 8.7 indicates a high severity. The EPSS score is below 1 percent, and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is the processing of a malicious TAR archive; any application that uses mtar_* functions to open or read TAR files is a potential vector. Based on the description, it is inferred that a crafted archive could exploit the overflow by supplying a name or linkname field that is not null‑terminated, causing strcpy to read past the intended boundary and leading to stack corruption or code execution. The absence of a publicly released fix increases the risk of exploitation in the wild.