How severe is CVE-2019-3870?

CVE-2019-3870 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.

Is CVE-2019-3870 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-3870?

CVE-2019-3870 primarily affects Samba. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-3870?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2019-3870 published?

CVE-2019-3870 was published on 2019-04-09 and last updated on 2026-06-17.

CVE-2019-3870

CVE-2019-3870 is a medium-severity vulnerability in Samba with a CVSS 3.x base score of 6.1. 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-276.

Key facts

Severity: Medium (CVSS 3.x base score 6.1)
CVSS v2: 3.6
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-276
Affected product: Samba
Published: 2019-04-09
Last modified: 2026-06-17

Description

A vulnerability was found in Samba from version (including) 4.9 to versions before 4.9.6 and 4.10.2. During the creation of a new Samba AD DC, files are created in a private subdirectory of the install location. This directory is typically mode 0700, that is owner (root) only access. However in some upgraded installations it will have other permissions, such as 0755, because this was the default before Samba 4.8. Within this directory, files are created with mode 0666, which is world-writable, including a sample krb5.conf, and the list of DNS names and servicePrincipalName values to update.

Frequently asked questions

What is CVE-2019-3870?: A vulnerability was found in Samba from version (including) 4.9 to versions before 4.9.6 and 4.10.2. During the creation of a new Samba AD DC, files are created in a private subdirectory of the install location. This directory is typically mode 0700, that is owner (root) only access. However in some upgraded installations it will have other permissions, such as 0755, because this was the default before Samba 4.8. Within this directory, files are created with mode 0666, which is world-writable, including a sample krb5.conf, and the list of DNS names and servicePrincipalName values to update.
How severe is CVE-2019-3870?: CVE-2019-3870 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability high.
Is CVE-2019-3870 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-3870?: CVE-2019-3870 primarily affects Samba. In total, 10 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2019-3870?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2019-3870 published?: CVE-2019-3870 was published on 2019-04-09 and last updated on 2026-06-17.

References

Affected products (10)

cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:29:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:30:*:*:*:*:*:*:*
cpe:2.3:a:synology:directory_server:-:*:*:*:*:*:*:*
cpe:2.3:a:synology:router_manager:1.2:*:*:*:*:*:*:*
cpe:2.3:o:synology:diskstation_manager:5.2:*:*:*:*:*:*:*
cpe:2.3:o:synology:diskstation_manager:6.1:*:*:*:*:*:*:*
cpe:2.3:o:synology:diskstation_manager:6.2:*:*:*:*:*:*:*
cpe:2.3:o:synology:skynas_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:synology:vs960hd_firmware:*:*:*:*:*:*:*:*

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