How severe is CVE-2018-20835?

CVE-2018-20835 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2018-20835 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20835?

CVE-2018-20835 affects Tar-fs Project Tar-fs. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-20835?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-20835 published?

CVE-2018-20835 was published on 2019-04-30 and last updated on 2026-06-17.

CVE-2018-20835

CVE-2018-20835 is a high-severity vulnerability in Tar-fs Project Tar-fs with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 6.4
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Tar-fs Project Tar-fs
Published: 2019-04-30
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2018-20835?: 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.
How severe is CVE-2018-20835?: CVE-2018-20835 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2018-20835 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20835?: CVE-2018-20835 affects Tar-fs Project Tar-fs. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-20835?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-20835 published?: CVE-2018-20835 was published on 2019-04-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:tar-fs_project:tar-fs:*:*:*:*:*:*:*:*

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