CVE-2026-55738 (GCVE-0-2026-55738)

Vulnerability from cvelistv5 – Published: 2026-06-17 13:45 – Updated: 2026-08-10 11:44
VLAI
Title
Stack Buffer Overflow in rxi/microtar raw_to_header() via non-null-terminated TAR name field
Summary
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.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-17 15:00 UTC
CWE
  • CWE-121 - Stack-based Buffer Overflow
  • CWE-170 - Improper Null Termination
Assigner
TuranSec CNA under the mitre root
CNA scorecard C 70/100 over 189 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
rxi microtar Affected: 0.1.0 (semver)
guessed Create a notification for this product.
Date Public
2026-06-17 13:45
Credits
Saidakbarxon Maxsudxonov
Show details on NVD website
To clipboard 

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How durations are calculated

Following the VTEM framework (Black Hat USA 2015), time to patch starts when the vendor or a coordinator was informed, total time to patch at discovery, and disclosure to patch at public disclosure; vendor response time runs from the report to its acknowledgement. Time to exploit and time unpatched start at the earliest discovery or report, falling back to public disclosure. Unpatched time ends at the first recorded patch, or the calculation time when no patch is recorded. Exploitation to patch shows the interval between those two events; a published proof of concept is a public exploit, not exploitation.

Each result shows its source dates. A negative interval means the end event came first; when date-only inputs leave the order open, the result says so. Date-only inputs are approximate. The earliest evidence wins: KEV report dates and sightings are labelled as such. Records describing another vulnerability are listed but never calculated from, and a PoC alone does not establish exploitation. Missing patch evidence does not prove that no patch exists. Filters below change the event list only.

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