CVE-2018-20482: debian debian_linux Infinite Loop
Vulnerability summary
CVE-2018-20482 is a medium (CVSS 4.7) Infinite Loop vulnerability in debian debian_linux. EPSS estimates a 0.53% chance of exploitation in the next 30 days, higher than 43.6% of scored vulnerabilities. 1 public exploit is recorded.
Advisory lineage
Upstream 0 · Downstream 7 · Related 7Timeline
- 26-12-2018PublishedVulnerability first disclosed.
- 14-10-2026Last modifiedVulnerability information updated.
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).
CVSS metrics
6 scores · 4 sources · 3 versions- OSV · AlpineEcosystem advisory · calculated4.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · UbuntuEcosystem advisory · calculated4.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated4.7MediumCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.53%
Chance of exploitation in the next 30 days
Percentile
44%
Versus all other CVEs
30-day change
0.00 pp
From 0.53% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundExploit Reference (news.ycombinator.com)
Maturity: unknown
Weaknesses
CWE · root causeAffected systems
Debian2 products
- tar< 1.29b-1.1+deb9u1 | < 1.27.1-2+deb8u2 | < 1.30+dfsg-3.1
- debian_linuxEOL8.0 | 9.0
Alpine1 product
- tar< 1.31-r0
Gnu1 product
- tar≤ 1.30
Mageia1 product
- tar< 1.31-1.mga6
Opensuse1 product
- leapEOL15.0
Ubuntu1 product
- tar< 1.27.1-1ubuntu0.1+esm1 | < 1.28-2.1ubuntu0.2 | < 1.29b-2ubuntu0.2
6 vendors · 7 products
References
19 links- utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBugX Refsource MISCPatchThird Party AdvisoryREPORT
- git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454X Refsource MISCPatchThird Party Advisory
lists.debian.org/debian-lts-announce/2018/12/msg00023.htmlMailing ListX Refsource MLISTThird Party Advisory- lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.htmlVendor AdvisoryX Refsource SUSEMailing ListThird Party Advisory
- lists.debian.org/debian-lts-announce/2021/11/msg00025.htmlMailing ListX Refsource MLISTThird Party Advisory