Bug 2370453 (CVE-2025-0620)

Summary: CVE-2025-0620 samba: smbd doesn't pick up group membership changes when re-authenticating an expired SMB session
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Samba. The smbd service daemon does not pick up group membership changes when re-authenticating an expired SMB session. This issue can expose file shares until clients disconnect and then connect again.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2370454, 2370455    
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Description OSIDB Bzimport 2025-06-05 16:34:30 UTC
All versions of Samba starting with 4.21.0 are vulnerable to a improper authorization issue. smbd does not pick up group membership changes when re-authenticating an expired SMB session.