Samba up to 4.14.x Metadata race condition

CVSS Meta Temp Score
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CTI Interest Score
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5.8$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Samba up to 4.14.x. This affects an unknown part of the component Metadata Handler. This manipulation causes race condition. This vulnerability is registered as CVE-2021-20316. Remote exploitation of the attack is possible. No exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in Samba up to 4.14.x (File Transfer Software). Affected by this vulnerability is some unknown functionality of the component Metadata Handler. The manipulation with an unknown input leads to a race condition vulnerability. The CWE definition for the vulnerability is CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in the way Samba handled file/directory metadata. This flaw allows an authenticated attacker with permissions to read or modify share metadata, to perform this operation outside of the share.

The weakness was published 08/24/2022. It is possible to read the advisory at samba.org. This vulnerability is known as CVE-2021-20316 since 12/17/2020. The technical details are unknown and an exploit is not publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 236698 (Alibaba Cloud Linux 3 : 0176: samba (ALINUX3-SA-2022:0176)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.15.0 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (236698). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.9
VulDB Meta Temp Score: 5.8

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.8
NVD Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Race condition
CWE: CWE-362
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236698
Nessus Name: Alibaba Cloud Linux 3 : 0176: samba (ALINUX3-SA-2022:0176)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Samba 4.15.0

Timelineinfo

12/17/2020 🔍
08/24/2022 +614 days 🔍
08/24/2022 +0 days 🔍
05/17/2025 +997 days 🔍

Sourcesinfo

Product: samba.org

Advisory: samba.org
Status: Confirmed

CVE: CVE-2021-20316 (🔍)
GCVE (CVE): GCVE-0-2021-20316
GCVE (VulDB): GCVE-100-207055

Entryinfo

Created: 08/24/2022 09:05
Updated: 05/17/2025 15:11
Changes: 08/24/2022 09:05 (40), 09/25/2022 08:59 (11), 05/17/2025 15:11 (16)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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