CVE-2023-34966

Samba: infinite loop in mdssvc rpc service for spotlight

HIGH
7.5
CVSS Score
Published: July 20, 2023 at 02:56 PM UTC
Updated: June 17, 2026 at 06:04 AM UTC
4 products affected across 4 vendorsDebian LinuxFedoraEnterprise Linux

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Severity
HIGH7.5
Exploit prediction
EPSS 62%

Description

An infinite loop vulnerability was found in Samba's mdssvc RPC service for Spotlight. When parsing Spotlight mdssvc RPC packets sent by the client, the core unmarshalling function sl_unpack_loop() did not validate a field in the network packet that contains the count of elements in an array-like structure. By passing 0 as the count value, the attacked function will run in an endless loop consuming 100% CPU. This flaw allows an attacker to issue a malformed RPC request, triggering an infinite loop, resulting in a denial of service condition.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Vendor states this is fixed in 0:4.15.5-15.el8_6 (unaffected)
Vendor states this is fixed in 0:4.17.5-105.el9_2 (unaffected)
Vendor states this is fixed in 0:4.17.5-5.el8_8 (unaffected)
Vendor states this is fixed in 0:4.18.6-1.el8 (unaffected)
Vendor states this is fixed in 0:4.18.6-100.el9 (unaffected)
Vendor states this is fixed in 6 (unknown)
Vendor states this is fixed in 7 (unknown)
v < 4.16.114.17.0 ≤ v < 4.17.104.18.0 ≤ v < 4.18.5
Affected range stops below 4.16.11, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.17.10, so it looks safe — our inference, not a vendor statement
Affected range stops below 4.18.5, so it looks safe — our inference, not a vendor statement

References (12)

Vendor Advisoryx_refsource_REDHATThird Party Advisory
https://access.redhat.com/errata/RHSA-2023:6667
Vendor Advisoryx_refsource_REDHATThird Party Advisory
https://access.redhat.com/errata/RHSA-2023:7139
VDB Entryx_refsource_REDHATThird Party Advisory
https://access.redhat.com/security/cve/CVE-2023-34966
Issue Trackingx_refsource_REDHATThird Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2222793

CVSS

7.5HIGHredhat
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-835

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