Skip to content
Fencer Vulns
high 7.5

CVE-2023-34966 in the critical feed json

Samba: infinite loop in mdssvc rpc service for spotlight

published 2023-07-20 3 y ago modified 2026-11-07 2 d ago also EUVD-2023-39005

cvss
7.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
62.4%
EPSS 62.4% chance of exploitation in 30 days, percentile 99.1%
public exploits
0
none known

Summary

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.

Patch / fix

  • Red Hat Red Hat Enterprise Linux 8 0:4.18.6-1.el8
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support 0:4.15.5-15.el8_6
  • Red Hat Red Hat Enterprise Linux 8.8 Extended Update Support 0:4.17.5-5.el8_8
  • Red Hat Red Hat Enterprise Linux 9 0:4.18.6-100.el9
  • Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support 0:4.17.5-105.el9_2
  • Red Hat Red Hat Virtualization 4 for Red Hat Enterprise Linux 8 0:4.15.5-15.el8_6
  • samba Debian 12 2:4.17.10+dfsg-0+deb12u1
  • samba Debian 14, Debian 13 2:4.18.5+dfsg-1

debian advisories DEBIAN-CVE-2023-34966

  • samba Ubuntu 20.04 LTS 2:4.15.13+dfsg-0ubuntu0.20.04.3
  • samba Ubuntu 22.04 LTS 2:4.15.13+dfsg-0ubuntu1.2
  • samba Ubuntu Pro 14.04 LTS 2:4.3.11+dfsg-0ubuntu0.14.04.20+esm13
  • samba Ubuntu Pro 16.04 LTS 2:4.3.11+dfsg-0ubuntu0.16.04.34+esm2
  • samba Ubuntu Pro 18.04 LTS 2:4.7.6+dfsg~ubuntu-0ubuntu2.29+esm1

ubuntu advisories UBUNTU-CVE-2023-34966

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • samba rhev hypervisor 4.4, RHEL 8.6 EUS 4.15.5-15.el8_6
  • libwbclient rhev hypervisor 4.4, RHEL 8.6 EUS 4.15.5-15.el8_6
  • libsmbclient rhev hypervisor 4.4, RHEL 8.6 EUS 4.15.5-15.el8_6
  • samba-common rhev hypervisor 4.4, RHEL 8.6 EUS 4.15.5-15.el8_6
  • samba RHEL 8 4.18.6-1.el8
  • ctdb RHEL 8 4.18.6-1.el8
  • libnetapi RHEL 8 4.18.6-1.el8
  • samba-libs RHEL 8 4.18.6-1.el8

red hat advisories RHSA-2024:0423RHSA-2024:4101RHSA-2024:0580RHSA-2023:7139RHSA-2023:6667

  • samba Enterprise Storage 7 4.13.13+git.643.8caa136952b-150200.3.26.3
  • samba SLES for SAP 15 SP3, SLES 15 SP3-LTSS, SLE Real Time 15 SP3 +7 more 4.15.13+git.663.9c654e06cdb-150300.3.57.5
  • samba SLE Module for Basesystem 15 SP4, SLE Micro 5.4, SLE Micro 5.3 +4 more 4.15.13+git.663.9c654e06cdb-150400.3.28.1
  • samba SLE Module for Basesystem 15 SP5, SLE High Availability Extension 15 SP5, openSUSE Leap 15.5 4.17.9+git.367.dae41ffdd1f-150500.3.5.1
  • samba SLES for SAP 12 SP5, SLES 12 SP5, SLE Software Development Kit 12 SP5 +1 more 4.15.13+git.621.c8ae836ff82-3.85.1

suse advisories SUSE-SU-2023:3066-1SUSE-SU-2023:3060-1SUSE-SU-2023:2930-1SUSE-SU-2023:2929-1SUSE-SU-2023:2888-1

  • samba openSUSE Tumbleweed 4.18.5+git.313.c8e274c7852-1.1

opensuse advisories openSUSE-SU-2024:13071-1

  • samba AlmaLinux 8 4.18.6-1.el8
  • ctdb AlmaLinux 8 4.18.6-1.el8
  • libnetapi AlmaLinux 8 4.18.6-1.el8
  • samba-libs AlmaLinux 8 4.18.6-1.el8
  • samba-pidl AlmaLinux 8 4.18.6-1.el8
  • samba-test AlmaLinux 8 4.18.6-1.el8
  • libwbclient AlmaLinux 8 4.18.6-1.el8
  • samba-tools AlmaLinux 8 4.18.6-1.el8

almalinux advisories ALSA-2023:7139ALSA-2023:6667

  • openchange Rocky Linux 8 2.3-32.el8
  • evolution-mapi Rocky Linux 8 3.28.3-8.el8

rocky linux advisories RLSA-2023:7139

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-34966 updated cvss 7.5

samba: infinite loop in mdssvc RPC service for spotlight

  • Red Hat Enterprise Linux 6 samba, samba4, samba4-dc, samba-swat, samba4-libs, samba4-pidl, +17 more Red Hat Enterprise Linux 7 ctdb, samba, samba-dc, ctdb-tests, samba-libs, samba-pidl, +18 more Red Hat Storage 3 ctdb, samba, samba-dc, ctdb-tests, samba-libs, samba-pidl, +21 more
    affected: workaround, no fix planned “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .”
  • Red Hat CodeReady Linux Builder (v. 8) samba-devel 4.18.6-1.el8, ctdb-debuginfo 4.18.6-1.el8, libnetapi-devel 4.18.6-1.el8, samba-debuginfo 4.18.6-1.el8, libwbclient-devel 4.18.6-1.el8, samba-debugsource 4.18.6-1.el8, +24 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2023:7139
  • Red Hat CodeReady Linux Builder (v. 9) samba-pidl 4.18.6-100.el9, samba-test 4.18.6-100.el9, samba-test-libs 4.18.6-100.el9, python3-samba-test 4.18.6-100.el9
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2023:6667
  • Red Hat CodeReady Linux Builder EUS (v.8.6) samba-devel 4.15.5-15.el8_6, ctdb-debuginfo 4.15.5-15.el8_6, samba-debuginfo 4.15.5-15.el8_6, libwbclient-devel 4.15.5-15.el8_6, samba-debugsource 4.15.5-15.el8_6, libsmbclient-devel 4.15.5-15.el8_6, +17 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:0423
  • Red Hat CodeReady Linux Builder EUS (v.8.8) samba-devel 4.17.5-5.el8_8, ctdb-debuginfo 4.17.5-5.el8_8, libnetapi-devel 4.17.5-5.el8_8, samba-debuginfo 4.17.5-5.el8_8, libwbclient-devel 4.17.5-5.el8_8, samba-debugsource 4.17.5-5.el8_8, +24 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:0580
  • Red Hat CodeReady Linux Builder EUS (v.9.2) samba-pidl 4.17.5-105.el9_2, samba-test 4.17.5-105.el9_2, samba-test-libs 4.17.5-105.el9_2, python3-samba-test 4.17.5-105.el9_2
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:4101
  • Red Hat Enterprise Linux AppStream (v. 8) samba-vfs-iouring 4.18.6-1.el8
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2023:7139
  • Red Hat Enterprise Linux AppStream (v. 9) samba-client 4.18.6-100.el9, samba-winexe 4.18.6-100.el9, samba-vfs-iouring 4.18.6-100.el9, samba-krb5-printing 4.18.6-100.el9, samba-winbind-clients 4.18.6-100.el9, samba-winbind-krb5-locator 4.18.6-100.el9
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2023:6667
show 12 more
  • Red Hat Enterprise Linux AppStream EUS (v.8.6) samba-vfs-iouring 4.15.5-15.el8_6
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:0423
  • Red Hat Enterprise Linux AppStream EUS (v.8.8) samba-vfs-iouring 4.17.5-5.el8_8
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:0580
  • Red Hat Enterprise Linux AppStream EUS (v.9.2) samba-client 4.17.5-105.el9_2, samba-winexe 4.17.5-105.el9_2, samba-vfs-iouring 4.17.5-105.el9_2, samba-krb5-printing 4.17.5-105.el9_2, samba-winbind-clients 4.17.5-105.el9_2, samba-winbind-krb5-locator 4.17.5-105.el9_2
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:4101
  • Red Hat Enterprise Linux BaseOS (v. 8) ctdb 4.18.6-1.el8, samba 4.18.6-1.el8, libnetapi 4.18.6-1.el8, samba-libs 4.18.6-1.el8, samba-pidl 4.18.6-1.el8, samba-test 4.18.6-1.el8, +22 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2023:7139
  • Red Hat Enterprise Linux BaseOS (v. 9) samba 4.18.6-100.el9, libnetapi 4.18.6-100.el9, samba-libs 4.18.6-100.el9, libwbclient 4.18.6-100.el9, samba-tools 4.18.6-100.el9, libsmbclient 4.18.6-100.el9, +12 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2023:6667
  • Red Hat Enterprise Linux BaseOS EUS (v.8.6) ctdb 4.15.5-15.el8_6, samba 4.15.5-15.el8_6, samba-libs 4.15.5-15.el8_6, samba-pidl 4.15.5-15.el8_6, samba-test 4.15.5-15.el8_6, libwbclient 4.15.5-15.el8_6, +15 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:0423
  • Red Hat Enterprise Linux BaseOS EUS (v.8.8) ctdb 4.17.5-5.el8_8, samba 4.17.5-5.el8_8, libnetapi 4.17.5-5.el8_8, samba-libs 4.17.5-5.el8_8, samba-pidl 4.17.5-5.el8_8, samba-test 4.17.5-5.el8_8, +22 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:0580
  • Red Hat Enterprise Linux BaseOS EUS (v.9.2) samba 4.17.5-105.el9_2, libnetapi 4.17.5-105.el9_2, samba-libs 4.17.5-105.el9_2, libwbclient 4.17.5-105.el9_2, samba-tools 4.17.5-105.el9_2, libsmbclient 4.17.5-105.el9_2, +12 more
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:4101
  • Red Hat Enterprise Linux Resilient Storage (v. 9) ctdb 4.18.6-100.el9
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2023:6667
  • Red Hat Enterprise Linux Resilient Storage EUS (v.9.2) ctdb 4.17.5-105.el9_2
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:4101
  • Red Hat Virtualization 4 Hypervisor for RHEL 8 samba 4.15.5-15.el8_6, libwbclient 4.15.5-15.el8_6, libsmbclient 4.15.5-15.el8_6, samba-common 4.15.5-15.el8_6, samba-client-libs 4.15.5-15.el8_6, samba-common-libs 4.15.5-15.el8_6
    fixed: vendor fix “As a possible workaround, disable Spotlight by removing all configuration stanzas ("spotlight=yes|true") that enable Spotlight .” RHSA-2024:0423
  • Red Hat Enterprise Linux AppStream (v. 8) openchange 2.3-32.el8, evolution-mapi 3.28.3-8.el8, evolution-mapi-langpacks 3.28.3-8.el8 Red Hat Enterprise Linux AppStream (v. 9) openchange 2.3-41.el9, evolution-mapi 3.40.1-6.el9, evolution-mapi-langpacks 3.40.1-6.el9
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

62.40% chance of exploitation in the next 30 days, higher than 99.1% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • Red Hat Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support
  • Red Hat Red Hat Enterprise Linux 8.8 Extended Update Support
  • Red Hat Red Hat Enterprise Linux 9
  • Red Hat Red Hat Enterprise Linux 9.2 Extended Update Support
  • Red Hat Red Hat Virtualization 4 for Red Hat Enterprise Linux 8
  • Red Hat Red Hat Enterprise Linux 6
  • Red Hat Red Hat Enterprise Linux 7
  • Red Hat Red Hat Storage 3

Classification

Weakness
  • CWE-835 Loop with Unreachable Exit Condition

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.