CVE-2018-20482 Denial of service in n/a

Medium 4.7 Published 26 Dec 2018 Updated 14 Oct 2026

Local attackers can cause a denial of service via infinite loop in GNU Tar when using sparse file support during archiving.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2018-20482?

CVE-2018-20482 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 26 Dec 2018. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

GNU Tar through 1.30, when --sparse is used, mishandles file shrinkage during read access, which allows local users to cause a denial of service (infinite read loop in sparse_dump_region in sparse.c) by modifying a file that is supposed to be archived by a different user's process (e.g., a system backup running as root).

Weakness: CWE-835

Which versions are affected by CVE-2018-20482?

It affects 3 products.

Products include Debian Debian Linux, Gnu Tar, Opensuse Leap.

How do I fix CVE-2018-20482?

Apply the vendor's patch.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2018-20482 being exploited?

There is no known exploitation of CVE-2018-20482 in the wild and no public exploit code.

All Debian Debian Linux vulnerabilities

Sources

Also known as ALPINE-CVE-2018-20482, DEBIAN-CVE-2018-20482, DLA-1623-1, DLA-2830-1, GHSA-pm5x-48pq-67cq, MGASA-2019-0034 and 1 more.