cbcvebase.
CVE-2023-3961
published 2023-11-03

CVE-2023-3961: A path traversal vulnerability was identified in Samba when processing client pipe names connecting to Unix domain sockets within a private directory. Samba…

PriorityP261critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
2.41%
82.3th percentile
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 traversal characters (../). This could result in SMB clients connecting as root to Unix domain sockets outside the private directory. If an attacker or client managed to send a pipe name resolving to an external service using an existing Unix domain socket, it could potentially lead to unauthorized access to the service and consequential adverse events, including compromise or service crashes.

Affected

12 ranges
VendorProductVersion rangeFixed in
debiansamba< samba 2:4.17.12+dfsg-0+deb12u1 (bookworm)samba 2:4.17.12+dfsg-0+deb12u1 (bookworm)
fedoraprojectfedora
paloaltopan-os
redhatenterprise_linux
redhatenterprise_linux_eus
redhatstorage
sambasamba< 4.17.124.17.12
sambasamba>= 0 < 2:4.17.12+dfsg-0+deb12u12:4.17.12+dfsg-0+deb12u1
sambasamba>= 0 < 2:4.19.1+dfsg-12:4.19.1+dfsg-1
sambasamba>= 0 < 2:4.19.1+dfsg-12:4.19.1+dfsg-1
sambasamba>= 4.18.0 < 4.18.84.18.8
sambasamba>= 4.19.0 < 4.19.14.19.1

Detection & IOCsextracted from sources · hover to see the quote

command../
  • Monitor SMB pipe name requests containing directory traversal sequences (../) targeting Unix domain socket paths outside the Samba private directory
  • Alert on smbd processes connecting as root to Unix domain sockets located outside the expected private directory
  • Inspect SMB RPC pipe name fields (e.g. in SAMR, LSA, SPOOLSS bind requests) for path traversal patterns that resolve outside the private socket directory
  • Watch for unexpected connections to arbitrary Unix domain sockets on the filesystem initiated by smbd running as root, which may indicate exploitation of this path traversal
  • ·Red Hat Enterprise Linux 6 (samba and samba4) and RHEL 7 (samba) are confirmed NOT affected; only specific versions require patching
  • ·No mitigation is available from Red Hat; patching is the only remediation path
  • ·The vulnerability is exploitable remotely over SMB (CVSS 9.8), making network-exposed Samba instances highest priority for patching

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv9.8CRITICAL
vendor_oracle9.8CRITICAL
vendor_debian9.1CRITICAL
vendor_redhat9.1CRITICAL
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