CVE-2018-20835
Improper Input Validation in tar-fs
A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- High
- Availability
- None
Exploit likelihood
What each source reports
NVD Score used
A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.
- Record
CVE-2018-20835- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - CVSS 2.0
- 6.4 Medium
AV:N/AC:L/Au:N/C:N/I:P/A:P - Weakness
- CWE-20
- Updated
- 2026-11-02
CVE List No score
A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.
- Record
CVE-2018-20835- Updated
- 2026-11-02
EUVDEUVD-2019-0483 No score
A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.
- Record
EUVD-2019-0483- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-x2mc-8fgj-3wmr
Improper Input Validation in tar-fs
A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.
- Record
GHSA-x2mc-8fgj-3wmr- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
OSV
A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.
- Record
CVE-2018-20835- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Updated
- 2026-11-02
OSVGHSA-x2mc-8fgj-3wmr
Improper Input Validation in tar-fs
A vulnerability was found in tar-fs before 1.16.2. An Arbitrary File Overwrite issue exists when extracting a tarball containing a hardlink to a file that already exists on the system, in conjunction with a later plain file with the same name as the hardlink. This plain file content replaces the existing file content.
- Record
GHSA-x2mc-8fgj-3wmr- CVSS 3.0
- 7.5 High
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - Weakness
- CWE-20
- Updated
- 2026-11-02
OSVCLSA-2026-1774484497 No score
TuxCare security update for tar-fs (5 CVEs)
TuxCare rebuilt tar-fs to address 5 CVEs. Fixed in 1.5.1-tuxcare.1.
- Record
CLSA-2026-1774484497- Updated
- 2026-11-02
Affected products
Affected packages
History
| Recorded | Changed | Sources |
|---|---|---|
| affected, facts | ||
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2018-20835 is a high vulnerability (CVSS 7.5) in Tar-fs Project Tar-fs, published April 30, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.36%, the 83rd percentile. Fixed in tar-fs 1.16.2.