CVE-2023-42669 | Samba: "rpcecho" development server allows denial of service via sleep() call on ad dc

A vulnerability was found in Samba's "rpcecho" development server, a non-Windows RPC server used to test Samba's DCE/RPC stack elements. This vulnerability stems from an RPC function that can be blocked indefinitely. The issue arises because the "rpcecho" service operates with only one worker in the main RPC task, allowing calls to the "rpcecho" server to be blocked for a specified time, causing service disruptions. This disruption is triggered by a "sleep()" call in the "dcesrv_echo_TestSleep()" function under specific conditions. Authenticated users or attackers can exploit this vulnerability to make calls to the "rpcecho" server, requesting it to block for a specified duration, effectively disrupting most services and leading to a complete denial of service on the AD DC. The DoS affects all other services as "rpcecho" runs in the main RPC task.

Published: 2023-11-06 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-42669 is rated Moderate Risk (53.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.72%). Core evidence: EPSS rose +1.14% over the last day, indicating growing attacker interest. Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-42669

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.58% 1.72% +1.14%
2 2025-11-28 0.50% 0.58% +0.08%
3 2025-11-23 0.50%

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-42669

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 3.6 [email protected]
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 3.6 [email protected]

Weakness enumeration for CVE-2023-42669

OS Trackers for CVE-2023-42669

vendor priority summary link
alpine medium CVE-2023-42669: 1 source package rows (samba); 7 state rows across 7 repos (3.17-main, 3.18-main, 3.19-main, 3.20-main, 3.21-main, 3.22-main, edge-main); fixed 6, open 1. https://security.alpinelinux.org/vuln/CVE-2023-42669
debian not yet assigned CVE-2023-42669 not yet assigned priority: Debian including 1 source packages (samba), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 4, open 1. https://security-tracker.debian.org/tracker/CVE-2023-42669
gentoo high CVE-2023-42669: 1 GLSA(s) (202402-28), 1 atom(s) (net-fs/samba); latest impact high. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2023-42669
redhat medium https://access.redhat.com/security/cve/CVE-2023-42669
suse medium https://www.suse.com/security/cve/CVE-2023-42669/
ubuntu medium CVE-2023-42669 medium priority: Ubuntu including 1 source packages (samba), 12 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): released 8, needs-triage 4. https://ubuntu.com/security/CVE-2023-42669

Affected software / configurations for CVE-2023-42669

Vendor Product Version Raw CPE
samba samba >= 4.0.0, < 4.17.12 cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*
samba samba >= 4.18.0, < 4.18.8 cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*
samba samba >= 4.19.0, < 4.19.1 cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:*
redhat storage 3.0 cpe:2.3:a:redhat:storage:3.0:*:*:*:*:*:*:*
redhat enterprise_linux 8.0 cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*
redhat enterprise_linux 9.0 cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
redhat enterprise_linux_eus 9.0 cpe:2.3:o:redhat:enterprise_linux_eus:9.0:*:*:*:*:*:*:*
redhat enterprise_linux_for_ibm_z_systems 9.0_s390x cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:9.0_s390x:*:*:*:*:*:*:*
redhat enterprise_linux_for_ibm_z_systems_eus 9.0_s390x cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:9.0_s390x:*:*:*:*:*:*:*
redhat enterprise_linux_for_power_little_endian 9.0_ppc64le cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:9.0_ppc64le:*:*:*:*:*:*:*
redhat enterprise_linux_for_power_little_endian_eus 9.0_ppc64le cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:9.0_ppc64le:*:*:*:*:*:*:*

References for CVE-2023-42669

cvelogic Threat Intelligence