CVE-2023-3961: A path traversal vulnerability was identified in Samba when processing client pipe names connecting to Unix do

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CRITICAL 9.1REMOTEWATCHLISTUPGRADEDOWNGRADEMITIGATE

CVE-2023-3961 is a critical-severity flaw (CVSS 9.1) affecting samba, storage, enterprise linux. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A path traversal vulnerability was identified in Samba when processing client pipe names connecting to Unix domain sockets within a private directory. Samba typically uses this mechanism to connect SMB clients to remote procedure call (RPC) services like SAMR LSA or SPOOLSS, which Samba initiates on demand. However, due to inadequate sanitization of incoming client pipe names, allowing a client to send a pipe name containing Unix directory traver

Why this priority

Critical severity
Public exploit reference
Remotely exploitable, no login, no user action
On your watchlist

A fixed release or distro patch exists.

Risk facts

CVSS score	9.1 (Critical)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	2.7% (top 14%)
CISA exploited list	No
Weakness	CWE-22
Published	2023-11-03
Last modified	2026-06-17

Publisher (CNA): Red Hat, Inc. · Vendor: fedoraproject · redhat · samba

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2023-11-03 13:15 UTCPublished CVE record published
2026-06-17 06:15 UTCUpdated Record last modified

samba samba UPGRADE

Affected: < 4.17.12 · >= 4.18.0 and < 4.18.8 · >= 4.19.0 and < 4.19.1

Fixed in: 4.17.12, 4.18.8, 4.19.1

Safe to downgrade to: a release before 4.18.0

1. Check installed version

apt-cache policy samba || rpm -q samba || samba --version

2. UPGRADE to 4.17.12 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade samba

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade samba

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

3. If no update is available yet, DOWNGRADE to a release before 4.18.0 (Debian / Ubuntu)

apt-cache madison samba sudo apt install samba=<VERSION_BEFORE_4.18.0> sudo apt-mark hold samba

3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list samba sudo dnf downgrade samba-<VERSION_BEFORE_4.18.0> sudo dnf versionlock add samba

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat storage DOWNGRADE

Affected: 3.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 3.0

1. Check installed version

apt-cache policy storage || rpm -q storage || storage --version

2. No fixed release: DOWNGRADE to a release before 3.0 (Debian / Ubuntu)

apt-cache madison storage sudo apt install storage=<VERSION_BEFORE_3.0> sudo apt-mark hold storage

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list storage sudo dnf downgrade storage-<VERSION_BEFORE_3.0> sudo dnf versionlock add storage

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

redhat enterprise linux MITIGATE

Affected: 8.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 8.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

redhat enterprise linux eus MITIGATE

Affected: 9.0

Fixed in: no fixed release known

Safe to downgrade to: a release before 9.0

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

fedoraproject fedora MITIGATE

Affected: 39

Fixed in: no fixed release known

Safe to downgrade to: a release before 39

Check your OS release

cat /etc/os-release; uname -r

Debian / Ubuntu

sudo apt update && sudo apt full-upgrade

RHEL / Amazon Linux / Fedora

sudo dnf upgrade --refresh

Windows

Install the latest cumulative update from Windows Update

If no patch exists yet

OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.

Exact fixes by distribution

A distro patch exists: prefer upgrading over downgrading.

Fedora 46 · borgmatic · FIXED · 2.2.0-1.fc46 · FEDORA-2026-041229e71b · source

sudo dnf upgrade --advisory=FEDORA-2026-041229e71b

Fedora ELN · pie · FIXED · 1.5.4-1.eln159 · FEDORA-2026-a2c0261d3a · source

sudo dnf upgrade --advisory=FEDORA-2026-a2c0261d3a

Ubuntu 20.04 · samba · NOT AFFECTED

Ubuntu 22.04 · samba · NOT AFFECTED

Debian 12 · samba · FIXED · 2:4.17.12+dfsg-0+deb12u1

sudo apt update && sudo apt install --only-upgrade samba dpkg --compare-versions "$(dpkg-query -W -f='${Version}' samba)" ge "2:4.17.12+dfsg-0+deb12u1" && echo PATCHED || echo STILL-VULNERABLE

Debian 13 · samba · FIXED · 2:4.19.1+dfsg-1

sudo apt update && sudo apt install --only-upgrade samba dpkg --compare-versions "$(dpkg-query -W -f='${Version}' samba)" ge "2:4.19.1+dfsg-1" && echo PATCHED || echo STILL-VULNERABLE

RHEL 8 · samba · FIXED · samba-4.18.6-2.el8_9

sudo dnf upgrade --advisory=RHSA-2023:7467 rpm -q samba

RHEL 8.6 Extended Update Support · samba · FIXED · samba-4.15.5-13.el8_6

sudo dnf upgrade --advisory=RHSA-2023:7408 rpm -q samba

RHEL 8.8 Extended Update Support · samba · FIXED · samba-4.17.5-4.el8_8

sudo dnf upgrade --advisory=RHSA-2023:7464 rpm -q samba

RHEL 9 · samba · FIXED · samba-4.18.6-101.el9_3

sudo dnf upgrade --advisory=RHSA-2023:6744 rpm -q samba

RHEL 9.0 Extended Update Support · samba · FIXED · samba-4.15.5-111.el9_0

sudo dnf upgrade --advisory=RHSA-2023:6209 rpm -q samba

Alpine 3.20 · samba · FIXED · samba-4.18.8-r0

apk add --upgrade samba apk info -v samba

Alpine 3.21 · samba · FIXED · samba-4.18.8-r0

apk add --upgrade samba apk info -v samba

Alpine 3.22 · samba · FIXED · samba-4.18.8-r0

apk add --upgrade samba apk info -v samba

Alpine 3.23 · samba · FIXED · samba-4.18.8-r0

apk add --upgrade samba apk info -v samba

Amazon Linux 2023 · see advisory · FIXED · ALAS2023-2023-416 · source

sudo dnf update --advisory=ALAS2023-2023-416

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2023-3961?

samba: upgrade to 4.17.12, 4.18.8, 4.19.1; storage: downgrade or apply the listed mitigation; enterprise linux: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2023-3961 being exploited?

CVE-2023-3961 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2023-3961 affect?

CVE-2023-3961 affects samba, storage, enterprise linux. Severity is critical (CVSS 9.1). A path traversal vulnerability was identified in Samba when processing client pipe names connecting to Unix domain sockets within a private directory. Samba typically uses this mechanism to connect SMB clients to remote procedure call (RPC)

How urgent is CVE-2023-3961?

Priority 68/100. Critical severity; Public exploit reference; Remotely exploitable, no login, no user action; On your watchlist

Software pages

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References

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