6.5

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

Modified
AliasesALPINE-CVE-2023-42669UBUNTU-CVE-2023-42669DEBIAN-CVE-2023-42669
Published 06-11-2023Last modified 20-11-2025

Vulnerability summary

CVE-2023-42669 is a medium (CVSS 6.5) Uncontrolled Resource Consumption vulnerability in redhat enterprise_linux. EPSS estimates a 1.94% chance of exploitation in the next 30 days, higher than 80.1% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 6.5, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.5/10
010
Medium · v3.1 (CVE.org)
EPSS score
1.94%
0%100%
Low · +0.22 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 13 · Related 6
DSA-5525-1MGASA-2023-0340OPENSUSE-SU-2024:13332-1RHSA-2023:6209RHSA-2023:6744RHSA-2023:7371

Timeline

  1. 06-11-2023
    PublishedVulnerability first disclosed.
  2. 20-11-2025
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

1.94%

Chance of exploitation in the next 30 days

Percentile

80%

Versus all other CVEs

30-day change

Increase +0.22 pp

From 1.72% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Redhat7 products
Alpine1 product
  • samba≥ 4.0.0, < 4.18.8-r0
Debian1 product
  • samba< 2:4.17.12+dfsg-0+deb12u1 | < 2:4.19.1+dfsg-1
Samba1 product
  • samba≥ 4.0.0, < 4.17.12 | ≥ 4.18.0, < 4.18.8 | ≥ 4.19.0, < 4.19.1
Ubuntu1 product
  • sambaAll versions (No fix recorded) | < 2:4.15.13+dfsg-0ubuntu0.20.04.6 | < 2:4.15.13+dfsg-0ubuntu1.5 | < 2:4.18.6+dfsg-1ubuntu2.1

5 vendors · 11 products

References

17 links
Show all 17 references