CVE-2026-55738

Received Received - Intake

Stack-Based Buffer Overflow in microtar

Publication date: 2026-06-17

Last updated on: 2026-08-10

Assigner: 309f9ea4-e3e9-4c6c-b79d-e8eb01244f2c

Description

A stack-based buffer overflow exists in the raw_to_header function in src/microtar.c in 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.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published

2026-06-17

Last Modified

2026-08-10

Generated

2026-08-17

AI Q&A

2026-06-17

EPSS Evaluated

2026-08-15

NVD

CVE-2026-55738

EUVD

EUVD-2026-37712

Affected Vendors & Products

Vendor	Product	Version / Range
rxi	microtar	0.1.0

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-170	The product does not terminate or incorrectly terminates a string or array with a null character or equivalent terminator.
CWE-121	A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).

Attack-Flow Graph

Executive Summary

This vulnerability is a stack-based buffer overflow in the raw_to_header() function of the rxi microtar 0.1.0 library. The function uses strcpy() to copy fixed-width fields (name and linkname) from a TAR header without ensuring the source string is null-terminated. Because the POSIX ustar format allows these fields to be fully filled with non-null bytes, a specially crafted TAR archive can cause strcpy() to read beyond the intended 512-byte buffer and write past the destination buffer. This leads to an out-of-bounds read and stack buffer overflow.

A remote attacker can exploit this by supplying a malicious TAR archive that is opened or parsed by vulnerable functions (mtar_open(), mtar_read_header(), or mtar_find()), potentially causing a denial of service (crash) or even arbitrary code execution.

Impact Analysis

This vulnerability can impact you by allowing a remote attacker to cause a denial of service through a crash when processing a malicious TAR archive. More seriously, it may allow the attacker to execute arbitrary code on your system, potentially leading to full system compromise.

Hi! I’m here to help you understand CVE-2026-55738. Ask me anything about the vulnerability, its impact, or mitigation strategies.

0/70