Vulnerability · Published Jun 1, 2026 · Assigned by VulnCheck

CVE-2026-43623microtar 0.1.0 Stack-Based Buffer Overflow via raw_to_header()

High 8.8

In plain English

A high-severity stack buffer overflow in microtar from rxi. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 42% of all known vulnerabilities).

Severity (CVSS 3.1)8.8High

Exploit odds (30 days)0.5%top 57.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

microtar through 0.1.0 contains a stack-based buffer overflow vulnerability in the raw_to_header() function in src/microtar.c that allows attackers to corrupt adjacent stack memory by supplying a crafted TAR archive with non-null-terminated name or linkname fields. The function uses strcpy() to copy 100-byte ustar format fields that lack null terminators, causing writes of up to 355 bytes into a 100-byte destination buffer when mtar_open(), mtar_find(), or mtar_read_header() process attacker-supplied TAR archives.

Affected products (as reported)

Vendor	Product	Versions
rxi	microtar	0 – through 0.1.0

Weakness: CWE-121 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References

https://github.com/rxi/microtar/issues/28 issue-tracking
https://github.com/rxi/microtar/issues/29 issue-tracking
https://github.com/rxi/microtar/issues/30 issue-tracking
https://www.vulncheck.com/advisories/microtar-stack-based-buffer-overflow-via-raw-to-header third-party-advisory