High severity · published Apr 30, 2019
CVE-2018-20834
A vulnerability was found in node-tar before version 4.4.2 (excluding version 2.2.2)
7.5
CVSS
3.1%
EPSS
No
On KEV
Description
A vulnerability was found in node-tar before version 4.4.2 (excluding version 2.2.2). 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. A patch has been applied to node-tar v2.2.2).
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)3.1% · higher than 88% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TA
Tar · Isaacs
before 2.2.2; 3.0.0 before 4.4.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-20834
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-20834
access.redhat.com
https://access.redhat.com/errata/RHSA-2019:1821
github.com
https://github.com/npm/node-tar/commit/7ecef07da6a9e72cc0c4d0c9c6a8e85b6b52395d
Patch
https://github.com/npm/node-tar/commit/b0c58433c22f5e7fe8b1c76373f27e3f81dcd4c8
github.com
https://github.com/npm/node-tar/commits/v2.2.2
Patch
https://github.com/npm/node-tar/compare/58a8d43...a5f7779
Exploit
https://hackerone.com/reports/344595
More from Tar
8.2
CVE-2026-24842
node-tar Vulnerable to Arbitrary File Creation/Overwrite via Hardlink Path Traversal
7.5
CVE-2026-59871
node-tar: Process crash via PAX numeric path type confusion
7.5
CVE-2026-59874
node-tar: Negative tar entry size causes infinite loop in archive replace
7.5
CVE-2026-59873
node-tar: Decompression/parse DoS via unlimited input
7.1
CVE-2026-26960
node-tar has Arbitrary File Read/Write via Hardlink Target Escape Through Symlink Chain in Extraction
