Quick answers
- Is CVE-2026-55738 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-55738 being exploited in the wild.
- How severe is CVE-2026-55738?
- High severity, with a CVSS score of 8.8, published 17 June 2026.
- Which products and versions are affected?
- Rxi Microtar 0.1.0.
- Is there a fix for CVE-2026-55738?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-55738 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-55738?
- Check whether you run Rxi Microtar at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A stack-based buffer overflow exists in the raw_to_header() function in src/microtar.c of rxi microtar 0.1.0. The vulnerability is caused by the use of strcpy() to copy the 100-byte 'name' and 'linkname' fields from a TAR header without ensuring the source fields are null-terminated. While the POSIX ustar format allows these fields to be fully populated, microtar fails to account for this, leading to an out-of-bounds read and subsequent stack overflow when processing a crafted archive. Attackers can trigger this via mtar_open(), mtar_read_header(), or mtar_find(). As of the advisory, no official patch is mentioned, though the issue is confirmed via AddressSanitizer.
Affected products
- rxi microtar 0.1.0
Timeline
- 2026-06-17: disclosed: Vulnerability published to NVD