Samba Bad Password Lockout race condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.7$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Samba. This affects an unknown function of the component Bad Password Lockout. Performing a manipulation results in race condition. This vulnerability is reported as CVE-2021-20251. The attack is possible to be carried out remotely. No exploit exists. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability classified as problematic has been found in Samba (File Transfer Software) (version now known). This affects some unknown processing of the component Bad Password Lockout. The manipulation with an unknown input leads to a race condition vulnerability. CWE is classifying the issue as 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. This is going to have an impact on confidentiality. The summary by CVE is:

A flaw was found in samba. A race condition in the password lockout code may lead to the risk of brute force attacks being successful if special conditions are met.

The weakness was disclosed 03/07/2023. The advisory is shared at bugzilla.redhat.com. This vulnerability is uniquely identified as CVE-2021-20251 since 12/17/2020. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 296132 (Azure Linux 3.0 Security Update: samba (CVE-2021-20251)), which helps to determine the existence of the flaw in a target environment.

Applying a patch is able to eliminate this problem. The bugfix is ready for download at bugzilla.redhat.com.

The vulnerability is also documented in the vulnerability database at Tenable (296132). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.8
VulDB Meta Temp Score: 4.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.9
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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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: 296132
Nessus Name: Azure Linux 3.0 Security Update: samba (CVE-2021-20251)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍

Patch: bugzilla.redhat.com

Timelineinfo

12/17/2020 🔍
03/07/2023 +810 days 🔍
03/07/2023 +0 days 🔍
01/23/2026 +1053 days 🔍

Sourcesinfo

Product: samba.org

Advisory: bugzilla.redhat.com
Status: Confirmed

CVE: CVE-2021-20251 (🔍)
GCVE (CVE): GCVE-0-2021-20251
GCVE (VulDB): GCVE-100-222417

Entryinfo

Created: 03/07/2023 08:11
Updated: 01/23/2026 17:02
Changes: 03/07/2023 08:11 (39), 04/01/2023 01:09 (11), 01/23/2026 17:02 (17)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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