CVE-2018-20482

Name: CVE-2018-20482
Creator: NVD / NIST
Published: 2018-12-26T18:29:00.373+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.7/10EPSS 0.53%

Last modified Jun 17, 2026

CVE-2018-20482 is a medium-severity vulnerability rated 4.7/10 on the CVSS scale. 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).. EPSS estimates a 0.53% chance of exploitation in the next 30 days.

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).

Metrics

CVSS 3.1

4.7/10

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.53%

40.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-835

Affected Software

Vendor	Product	Versions
Gnu	Tar	<= 1.30
Debian	Debian Linux	8.0
Debian	Debian Linux	9.0
Opensuse	Leap	15.0

References

http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454Patch, Third Party Advisory
http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.htmlThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.htmlMailing List, Third Party Advisory
http://www.securityfocus.com/bid/106354Third Party Advisory, VDB Entry
https://lists.debian.org/debian-lts-announce/2018/12/msg00023.htmlMailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/11/msg00025.htmlMailing List, Third Party Advisory
https://news.ycombinator.com/item?id=18745431Exploit, Third Party Advisory
https://security.gentoo.org/glsa/201903-05Third Party Advisory
https://twitter.com/thatcks/status/1076166645708668928Patch, Third Party Advisory
https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBugPatch, Third Party Advisory
http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454Patch, Third Party Advisory
http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.htmlThird Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.htmlMailing List, Third Party Advisory
http://www.securityfocus.com/bid/106354Third Party Advisory, VDB Entry
https://lists.debian.org/debian-lts-announce/2018/12/msg00023.htmlMailing List, Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/11/msg00025.htmlMailing List, Third Party Advisory
https://news.ycombinator.com/item?id=18745431Exploit, Third Party Advisory
https://security.gentoo.org/glsa/201903-05Third Party Advisory
https://twitter.com/thatcks/status/1076166645708668928Patch, Third Party Advisory
https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBugPatch, Third Party Advisory

Timeline

Published: Dec 26, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2018-20482?

How severe is CVE-2018-20482?

CVE-2018-20482 has a CVSS score of 4.7/10 (MEDIUM severity). The EPSS model estimates a 0.53% probability of exploitation in the next 30 days.

How do I fix CVE-2018-20482?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2018-20482?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST