CVE-2025-0620
Samba: smbd doesn't pick up group membership changes when re-authenticating an expired smb session
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- High
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Samba: smbd doesn't pick up group membership changes when re-authenticating an expired smb session
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.
- Record
CVE-2025-0620- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-552
- Updated
- 2026-11-05
EUVDEUVD-2025-17307
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.
- Record
EUVD-2025-17307- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-05
GitHub AdvisoriesGHSA-8q8w-8225-6gq4
A flaw was found in Samba. The smbd service daemon does not pick up group membership changes when...
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.
- Record
GHSA-8q8w-8225-6gq4- CVSS 3.1
- 6.6 Medium
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-552
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2025-0620- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-552
- Updated
- 2026-11-05
OSVALPINE-CVE-2025-0620
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.
- Record
ALPINE-CVE-2025-0620- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSV
Samba: smbd doesn't pick up group membership changes when re-authenticating an expired smb session
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.
- Record
CVE-2025-0620- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N - Weakness
- CWE-552
- Updated
- 2026-11-07
Show 6 moreShow less
OSVDEBIAN-CVE-2025-0620
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.
- Record
DEBIAN-CVE-2025-0620- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVUBUNTU-CVE-2025-0620
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.
- Record
UBUNTU-CVE-2025-0620- CVSS 3.1
- 4.9 Medium
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N - Updated
- 2026-11-02
OSVCLSA-2026-1778859875 No score
samba: Fix of CVE-2025-0620
- Fix CVE-2025-0620: smbd doesn't pick up group membership changes when re-authenticating an expired SMB session.
- Record
CLSA-2026-1778859875- Updated
- 2026-11-02
OSVopenSUSE-SU-2025:15296-1 No score
ctdb-4.22.2+git.396.c752843dcf4-1.1 on GA media
These are all security issues fixed in the ctdb-4.22.2+git.396.c752843dcf4-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2025:15296-1- Updated
- 2026-11-02
OSVSUSE-SU-2025:02230-1 No score
Security update for samba
This update for samba fixes the following issues:
- CVE-2025-0620: smbd doesn't pick up group membership changes when re-authenticating an expired SMB session (bsc#1244136).
Other bugfixes:
- net ad join fails with 'Failed to join domain: failed to create kerberos keytab' (bsc#1238063).
- Record
SUSE-SU-2025:02230-1- Updated
- 2026-11-02
OSVUSN-7564-1 No score
samba vulnerability
It was discovered that Samba incorrectly handled certain group membership changes when using Kerberos authentication. A remote user could possibly use this issue to continue to access resources after being removed by an administrator.
- Record
USN-7564-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
sambaAlpine:v3.22 |
4.21.0 up to 4.21.6-r0 | 4.21.6-r0 |
sambaAlpine:v3.23 |
4.21.0 up to 4.21.6-r0 | 4.21.6-r0 |
sambaAlpine:v3.24 |
4.21.0 up to 4.21.6-r0 | 4.21.6-r0 |
ctdbTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
ldb-toolsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
libldbTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
libldb-develTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
libnetapiTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
libnetapi-develTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
libsmbclientTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
Show 37 moreShow less
| Package | Affected | Fixed |
|---|---|---|
libsmbclient-develTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
libwbclientTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
libwbclient-develTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
python3-ldbTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
python3-sambaTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
python3-samba-dcTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
python3-samba-testTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
sambaTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-clientTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-client-libsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-commonTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-common-libsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-common-toolsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-dc-libsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-dcerpcTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-develTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-gpupdateTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-krb5-printingTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-ldb-ldap-modulesTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-libsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-pidlTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-testTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-test-libsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-toolsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-usersharesTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-vfs-iouringTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-winbindTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-winbind-clientsTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-winbind-krb5-locatorTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-winbind-modulesTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
samba-winexeTuxCare:AlmaLinux:9.6 |
before 4.21.3-14.el9_6.tuxcare.els1 | 4.21.3-14.el9_6.tuxcare.els1 |
sambaDebian:13 |
before 2:4.22.2+dfsg-1 | 2:4.22.2+dfsg-1 |
sambaDebian:14 |
before 2:4.22.2+dfsg-1 | 2:4.22.2+dfsg-1 |
sambaSUSE:Linux Enterprise Module for Basesystem 15 SP7 |
before 4.21.6+git.402.80f493f530f-150700.3.3.1 | 4.21.6+git.402.80f493f530f-150700.3.3.1 |
sambaSUSE:Linux Enterprise High Availability Extension 15 SP7 |
before 4.21.6+git.402.80f493f530f-150700.3.3.1 | 4.21.6+git.402.80f493f530f-150700.3.3.1 |
sambaUbuntu:25.04 |
before 2:4.21.4+dfsg-1ubuntu3.1, plus listed versions 2:4.20.4+dfsg-1ubuntu12:4.20.4+dfsg-1ubuntu22:4.20.4+dfsg-1ubuntu32:4.20.4+dfsg-1ubuntu52:4.21.4+dfsg-1ubuntu22:4.21.4+dfsg-1ubuntu3 |
2:4.21.4+dfsg-1ubuntu3.1 |
sambaopenSUSE:Tumbleweed |
before 4.22.2+git.396.c752843dcf4-1.1 | 4.22.2+git.396.c752843dcf4-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | CVE List, EUVD | |
| affected | ||
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2025-0620 is a medium vulnerability (CVSS 4.9) in Samba, published June 3, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.80%, the 56th percentile. Fixed in samba 4.21.6-r0.
References
access.redhat.com/security/cve/CVE-2025-0620
bugzilla.redhat.com/show_bug.cgi?id=2370453
samba.org/samba/security/CVE-2025-0620.html
openwall.com/lists/oss-security/2025/06/03/8
nvd.nist.gov/vuln/detail/CVE-2025-0620
github.com/advisories/GHSA-8q8w-8225-6gq4
Show 13 moreShow less
security.alpinelinux.org/vuln/CVE-2025-0620
errata.tuxcare.com/els_os/tuxcare9.6esu/CLSA-2026-1778859875.html
security-tracker.debian.org/tracker/CVE-2025-0620
suse.com/support/update/announcement/2025/suse-su-202502230-1
bugzilla.suse.com/1238063
ubuntu.com/security/CVE-2025-0620
cve.org/CVERecord?id=CVE-2025-0620