dbcve.org
StorageApplication · Redhat

CVE-2020-10730

MEDIUM · 6.5 CVSS v3.1 Published 2020-07-07
Fix available
A fix is available. Upgrade to 4.10.17 / 4.11.11 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A NULL pointer dereference, or possible use-after-free flaw was found in Samba AD LDAP server in versions before 4.10.17, before 4.11.11 and before 4.12.4. Although some versions of Samba shipped with Red Hat Enterprise Linux do not support Samba in AD mode, the affected code is shipped with the libldb package. This flaw allows an authenticated user to possibly trigger a use-after-free or NULL pointer dereference. The highest threat from this vulnerability is to system availability.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

A NULL pointer dereference or possible use-after-free vulnerability exists in Samba AD LDAP server's libldb package in versions before 4.10.17, 4.11.11, and 4.12.4. An authenticated user can trigger this flaw, causing a denial of service impact to system availability.

MitigationUpgrade Samba to version 4.10.17, 4.11.11, 4.12.4 or later to address the NULL pointer dereference/use-after-free in libldb. If Samba AD mode is not required, ensure the affected libldb code is not exposed to authenticated users.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
StorageApplication
Affected:= 3.0
FedoraOperating system
Affected:= 31
Debian LinuxOperating system
Affected:= 9.0= 10.0
SambaApplication
Affected:>= 4.5.0, < 4.10.17>= 4.11.0, < 4.11.11>= 4.12.0, < 4.12.4
LeapOperating system
Affected:= 15.1= 15.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Samba version
    Run 'samba --version' or 'rpm -q samba' / 'dpkg -l samba' to obtain the installed Samba version.
    Affected if Version is < 4.10.17, < 4.11.11, or < 4.12.4 while >= 4.5.0.
  2. Verify Samba AD mode is enabled
    Inspect /etc/samba/smb.conf and look for 'server role = active directory domain controller' or check if 'samba' process is running as an AD DC.
    Affected if Samba AD domain controller mode is active, exposing the vulnerable libldb code in the AD LDAP server.
  3. Confirm libldb package version
    Run 'rpm -q ldb' or 'dpkg -l ldb' to check the libldb version bundled with or used by Samba.
    Affected if The libldb version corresponds to the vulnerable Samba version ranges.
  4. Check if LDAP server for AD is exposed
    Review network listeners (netstat -tlnp | grep -E 'ldap|samba') to confirm the AD LDAP server port (389/tcp) is open and accepting connections.
    Affected if The AD LDAP server is listening and accessible to authenticated users, allowing them to trigger the flaw.

The system is affected if Samba version falls within the vulnerable ranges AND Samba AD mode is enabled with the LDAP server exposed to authenticated users.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Upgrade available Upgrade to 4.10.17 / 4.11.11 / 4.12.4 or later
Fixed in 4.10.174.11.114.12.4
Interim mitigation

Upgrade Samba to version 4.10.17, 4.11.11, 4.12.4 or later to address the NULL pointer dereference/use-after-free in libldb. If Samba AD mode is not required, ensure the affected libldb code is not exposed to authenticated users.

Fix this in Storage Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-10730 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-10730 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data