Vulnerability in Ayuhito Modern-Tar
CVE-2026-109380
modern-tar 0.3.5 through 0.8.5 contains a memory exhaustion vulnerability that allows attackers to produce negative entry sizes via non-octal bytes parsed by readOctal(). Attackers can supply a crafted, optionally gzip-compressed, archive to unpackTar() that buffers chunks indefinitely, exhausting process memory and suppressing later entries.
Published .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/ayuhito/modern-tar/pull/195 (issue-tracking, patch)
- github.com/ayuhito/modern-tar/commit/181c8cb75351867535057817ada4802a90fe416e (patch)
- github.com/ayuhito/modern-tar/blob/v0.8.5/src/tar/encoding.ts (technical-description)
- github.com/ayuhito/modern-tar (product)
- www.vulncheck.com/advisories/modern-tar-0.3.5-through-0.8.5-memory-exhaustion-v… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-109380?
- CVE-2026-109380 is a high-severity vulnerability in Ayuhito Modern-Tar, classified under Improper Validation of Specified Quantity in Input. CVSS score: 7.5/10. Published 2026-10-12.
- How severe is CVE-2026-109380?
- High severity. CVSS v3 base score is 7.5 out of 10.