CVE-2018-20834

mediumpriority · track · 31EPSS 0.031 · 88 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

3.15% (88th) EPSS

CVSS 6.4 · medium

Is it mine?

12 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.4–7.5

v2.06.4mediumAV:N/AC:L/Au:N/C:N/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 4.9

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · OSV

v3.06.9mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:Nsecondary · FSTEC (BDU) RU

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-59USprimaryCWE-59USCWE-59US

affected products (12)

Products and version ranges known to be affected.

Juniper JUNOSall versionscert_bundDEcpe:/o:juniper:junos:-
n/a n/a≤ n/aenisa_euvdEU
Node.js Foundation node-tar≤ 2.2.2fstec_bduRU
Node.js Foundation node-tar3.0.0 → 4.4.2fstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7fstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7.5 EUSfstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7.6 EUSfstec_bduRU
Red Hat Inc. Red Hat Enterprise Linux≤ 7.4 EUSfstec_bduRU
isaacs tar< 2.2.2nvdUScpe:2.3:a:isaacs:tar:*:*:*:*:*:*:*:*
isaacs tar3.0.0 → 4.4.2nvdUScpe:2.3:a:isaacs:tar:*:*:*:*:*:*:*:*
npm tar< 2.2.2osvUSpkg:npm/tar
npm tar3.0.0 → 4.4.2osvUSpkg:npm/tar

advisories (3)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-2535Red Hat rh-nodejs8-nodejs: Mehrere SchwachstellenDeutsch2019-07-22csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Red Hat rh-nodejs8-nodejs ausnutzen, um Dateien zu manipulieren.
WID-SEC-W-2024-1591Juniper JUNOS: Mehrere SchwachstellenDeutsch2024-07-10csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.
GHSA-j44m-qm6p-hp7mArbitrary File Overwrite in tar2019-05-01ghsa · osvUS
Versions of `tar` prior to 4.4.2 for 4.x and 2.2.2 for 2.x are vulnerable to Arbitrary File Overwrite. Extracting tarballs containing a hardlink to a file that already exists in the system, and a file that matches the hardlink will overwrite the system's file with the contents of the extracted file. ## Recommendation For tar 4.x, upgrade to version 4.4.2 or later. For tar 2.x, upgrade to version 2.2.2 or later.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd osv NVD CVE.org MITRE

published 2019-04-30modified 2026-06-17

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references (24)

External citations — patches, advisories, analysis.

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