Samba: "rpcecho" development server allows denial of service via sleep() call on ad dc
Priority LOW 33CWE-400Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Partial Red Hat: 22 fixed, 3 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-400.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01941 80th percentileScored 2026-11-07
Fix Partial samba: 4.17.12, 4.18.8Red Hat: 6 advisoriesRed Hat: 22 fixed, 3 without a fix
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | samba | 4.0.0 to before 4.17.12; 4.18.0 to before 4.18.8; 4.19.0 | 4.17.12, 4.18.8 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | 4.18.6-2.el8_9 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8 | — | 4.18.6-2.el8_9 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support | — | 4.15.5-13.el8_6 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 8.8 Extended Update Support | — | 4.17.5-4.el8_8 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | 4.18.6-101.el9_3 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9 | — | 4.18.6-101.el9_3 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.0 Extended Update Support | — | 4.15.5-111.el9_0 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 9.2 Extended Update Support | — | 4.17.5-104.el9_2 | Patch available | CNA |
| Red Hat | Red Hat Virtualization 4 for Red Hat Enterprise Linux 8 | — | 4.15.5-13.el8_6 | Patch available | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 6 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Enterprise Linux 7 | — | — | No fix listed | CNA |
| Red Hat | Red Hat Storage 3 | — | — | No fix listed | CNA |
- samba Vendor— Affected 4.0.0 to before 4.17.12; 4.18.0 to before 4.18.8; 4.19.0 Fixed in 4.17.12, 4.18.8 Patch available CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in 4.18.6-2.el8_9 Patch available CNA
- Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in 4.18.6-2.el8_9 Patch available CNA
- Red Hat Enterprise Linux 8.6 Extended Update Support VendorRed Hat Affected — Fixed in 4.15.5-13.el8_6 Patch available CNA
- Red Hat Enterprise Linux 8.8 Extended Update Support VendorRed Hat Affected — Fixed in 4.17.5-4.el8_8 Patch available CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in 4.18.6-101.el9_3 Patch available CNA
- Red Hat Enterprise Linux 9 VendorRed Hat Affected — Fixed in 4.18.6-101.el9_3 Patch available CNA
- Red Hat Enterprise Linux 9.0 Extended Update Support VendorRed Hat Affected — Fixed in 4.15.5-111.el9_0 Patch available CNA
- Red Hat Enterprise Linux 9.2 Extended Update Support VendorRed Hat Affected — Fixed in 4.17.5-104.el9_2 Patch available CNA
- Red Hat Virtualization 4 for Red Hat Enterprise Linux 8 VendorRed Hat Affected — Fixed in 4.15.5-13.el8_6 Patch available CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 6 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Enterprise Linux 7 VendorRed Hat Affected — Fixed in — No fix listed CNA
- Red Hat Storage 3 VendorRed Hat Affected — Fixed in — No fix listed CNA
CPE configurations NVD · 9
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:* | 4.0.0 to before 4.17.12; 4.18.0 to before 4.18.8; 4.19.0 to before 4.19.1 | Vulnerable | Samba |
| cpe:2.3:a:redhat:storage:3.0:*:*:*:*:*:*:* | 3.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* | 8.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_eus:9.0:*:*:*:*:*:*:* | 9.0 | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:9.0_s390x:*:*:*:*:*:*:* | 9.0_s390x | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:9.0_s390x:*:*:*:*:*:*:* | 9.0_s390x | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:9.0_ppc64le:*:*:*:*:*:*:* | 9.0_ppc64le | Vulnerable | Red Hat |
| cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:9.0_ppc64le:*:*:*:*:*:*:* | 9.0_ppc64le | Vulnerable | Red Hat |
- cpe:2.3:a:samba:samba:*:*:*:*:*:*:*:* Versions 4.0.0 to before 4.17.12; 4.18.0 to before 4.18.8; 4.19.0 to before 4.19.1 Vulnerable ·Samba
- cpe:2.3:a:redhat:storage:3.0:*:*:*:*:*:*:* Versions 3.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:* Versions 8.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_eus:9.0:*:*:*:*:*:*:* Versions 9.0 Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems:9.0_s390x:*:*:*:*:*:*:* Versions 9.0_s390x Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_for_ibm_z_systems_eus:9.0_s390x:*:*:*:*:*:*:* Versions 9.0_s390x Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian:9.0_ppc64le:*:*:*:*:*:*:* Versions 9.0_ppc64le Vulnerable ·Red Hat
- cpe:2.3:o:redhat:enterprise_linux_for_power_little_endian_eus:9.0_ppc64le:*:*:*:*:*:*:* Versions 9.0_ppc64le Vulnerable ·Red Hat
Remediation
- Fix · CNA samba Fixed in 4.17.12, 4.18.8
Red Hat 6 advisories
- RHSA-2023:7467 Released 2023-11-22 · Red Hat rating Moderatesamba security update
- Red Hat CodeReady Linux Builder (v. 8) libnetapi-devel-4.18.6-2.el8_9, libsmbclient-devel-4.18.6-2.el8_9, libwbclient-devel-4.18.6-2.el8_9 +2
- Red Hat Enterprise Linux AppStream (v. 8) samba-vfs-iouring-4.18.6-2.el8_9
- Red Hat Enterprise Linux BaseOS (v. 8) ctdb-4.18.6-2.el8_9, libnetapi-4.18.6-2.el8_9, libsmbclient-4.18.6-2.el8_9 +25
- RHSA-2023:7464 Released 2023-11-22 · Red Hat rating Moderatesamba security update
- Red Hat CodeReady Linux Builder EUS (v.8.8) libnetapi-devel-4.17.5-4.el8_8, libsmbclient-devel-4.17.5-4.el8_8, libwbclient-devel-4.17.5-4.el8_8 +2
- Red Hat Enterprise Linux AppStream EUS (v.8.8) samba-vfs-iouring-4.17.5-4.el8_8
- Red Hat Enterprise Linux BaseOS EUS (v.8.8) ctdb-4.17.5-4.el8_8, libnetapi-4.17.5-4.el8_8, libsmbclient-4.17.5-4.el8_8 +25
- RHSA-2023:7408 Released 2023-11-21 · Red Hat rating Moderatesamba security update
- Red Hat CodeReady Linux Builder EUS (v.8.6) libsmbclient-devel-4.15.5-13.el8_6, libwbclient-devel-4.15.5-13.el8_6, samba-devel-4.15.5-13.el8_6
- Red Hat Enterprise Linux AppStream EUS (v.8.6) samba-vfs-iouring-4.15.5-13.el8_6
- Red Hat Enterprise Linux BaseOS EUS (v.8.6) ctdb-4.15.5-13.el8_6, libsmbclient-4.15.5-13.el8_6, libwbclient-4.15.5-13.el8_6 +18
- Red Hat Virtualization 4 Hypervisor for RHEL 8 libsmbclient-4.15.5-13.el8_6, libwbclient-4.15.5-13.el8_6, samba-4.15.5-13.el8_6 +3
Show 3 more Red Hat advisories
- RHSA-2023:7371 Released 2023-11-21 · Red Hat rating Moderatesamba security update
- Red Hat CodeReady Linux Builder EUS (v.9.2) libnetapi-devel-4.17.5-104.el9_2, libsmbclient-devel-4.17.5-104.el9_2, libwbclient-devel-4.17.5-104.el9_2 +6
- Red Hat Enterprise Linux AppStream EUS (v.9.2) samba-client-4.17.5-104.el9_2, samba-krb5-printing-4.17.5-104.el9_2, samba-vfs-iouring-4.17.5-104.el9_2 +3
- Red Hat Enterprise Linux BaseOS EUS (v.9.2) libnetapi-4.17.5-104.el9_2, libsmbclient-4.17.5-104.el9_2, libwbclient-4.17.5-104.el9_2 +15
- Red Hat Enterprise Linux Resilient Storage EUS (v.9.2) ctdb-4.17.5-104.el9_2
- RHSA-2023:6744 Released 2023-11-07 · Red Hat rating Moderatesamba security update
- Red Hat CodeReady Linux Builder (v. 9) libnetapi-devel-4.18.6-101.el9_3, libsmbclient-devel-4.18.6-101.el9_3, libwbclient-devel-4.18.6-101.el9_3 +6
- Red Hat Enterprise Linux AppStream (v. 9) samba-client-4.18.6-101.el9_3, samba-krb5-printing-4.18.6-101.el9_3, samba-vfs-iouring-4.18.6-101.el9_3 +3
- Red Hat Enterprise Linux BaseOS (v. 9) libnetapi-4.18.6-101.el9_3, libsmbclient-4.18.6-101.el9_3, libwbclient-4.18.6-101.el9_3 +15
- Red Hat Enterprise Linux Resilient Storage (v. 9) ctdb-4.18.6-101.el9_3
- RHSA-2023:6209 Released 2023-10-31 · Red Hat rating Moderatesamba security update
- Red Hat CodeReady Linux Builder EUS (v.9.0) libsmbclient-devel-4.15.5-111.el9_0, libwbclient-devel-4.15.5-111.el9_0, samba-devel-4.15.5-111.el9_0 +3
- Red Hat Enterprise Linux AppStream EUS (v.9.0) samba-client-4.15.5-111.el9_0, samba-krb5-printing-4.15.5-111.el9_0, samba-vfs-iouring-4.15.5-111.el9_0 +3
- Red Hat Enterprise Linux BaseOS EUS (v.9.0) libsmbclient-4.15.5-111.el9_0, libwbclient-4.15.5-111.el9_0, python3-samba-4.15.5-111.el9_0 +8
- Red Hat Enterprise Linux Resilient Storage EUS (v.9.0) ctdb-4.15.5-111.el9_0
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Advisory ·
Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 and 8 more products — RHSA-2023:6209
3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2023-03679 Samba: smbd allows client access to unix domain sockets on the file system as rootPriority MEDIUM 47
- TI-2023-03787 Samba: smb clients can truncate files with read-only permissionsPriority LOW 34
- Advisory ·
Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 and 8 more products — RHSA-2023:6744
3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2023-03679 Samba: smbd allows client access to unix domain sockets on the file system as rootPriority MEDIUM 47
- TI-2023-03787 Samba: smb clients can truncate files with read-only permissionsPriority LOW 34
Show 4 more groups
- Advisory ·
Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 and 8 more products — RHSA-2023:7371
3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2023-03679 Samba: smbd allows client access to unix domain sockets on the file system as rootPriority MEDIUM 47
- TI-2023-03787 Samba: smb clients can truncate files with read-only permissionsPriority LOW 34
- Advisory ·
Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 and 8 more products — RHSA-2023:7408
3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2023-03679 Samba: smbd allows client access to unix domain sockets on the file system as rootPriority MEDIUM 47
- TI-2023-03787 Samba: smb clients can truncate files with read-only permissionsPriority LOW 34
- Advisory ·
Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 and 8 more products — RHSA-2023:7464
3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2023-03679 Samba: smbd allows client access to unix domain sockets on the file system as rootPriority MEDIUM 47
- TI-2023-03787 Samba: smb clients can truncate files with read-only permissionsPriority LOW 34
- Advisory ·
Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7 and 8 more products — RHSA-2023:7467
3 records Highest priority Priority MEDIUM 1 MEDIUM, 2 LOW
Other records, highest priority first
- TI-2023-03679 Samba: smbd allows client access to unix domain sockets on the file system as rootPriority MEDIUM 47
- TI-2023-03787 Samba: smb clients can truncate files with read-only permissionsPriority LOW 34
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix planned: Out of support scope |
| Red Hat Storage 3 | Affected | No fix planned: Out of support scope |
| Red Hat CodeReady Linux Builder (v. 8) | Fixed | RHSA-2023:7467 |
| Red Hat CodeReady Linux Builder (v. 9) | Fixed | RHSA-2023:6744 |
| Red Hat CodeReady Linux Builder EUS (v.8.6) | Fixed | RHSA-2023:7408 |
| Red Hat CodeReady Linux Builder EUS (v.8.8) | Fixed | RHSA-2023:7464 |
| Red Hat CodeReady Linux Builder EUS (v.9.0) | Fixed | RHSA-2023:6209 |
| Red Hat CodeReady Linux Builder EUS (v.9.2) | Fixed | RHSA-2023:7371 |
| Red Hat Enterprise Linux AppStream (v. 8) | Fixed | RHSA-2023:7467 |
| Red Hat Enterprise Linux AppStream (v. 9) | Fixed | RHSA-2023:6744 |
| Red Hat Enterprise Linux AppStream EUS (v.8.6) | Fixed | RHSA-2023:7408 |
| Red Hat Enterprise Linux AppStream EUS (v.8.8) | Fixed | RHSA-2023:7464 |
| Red Hat Enterprise Linux AppStream EUS (v.9.0) | Fixed | RHSA-2023:6209 |
| Red Hat Enterprise Linux AppStream EUS (v.9.2) | Fixed | RHSA-2023:7371 |
| Red Hat Enterprise Linux BaseOS (v. 8) | Fixed | RHSA-2023:7467 |
| Red Hat Enterprise Linux BaseOS (v. 9) | Fixed | RHSA-2023:6744 |
| Red Hat Enterprise Linux BaseOS EUS (v.8.6) | Fixed | RHSA-2023:7408 |
| Red Hat Enterprise Linux BaseOS EUS (v.8.8) | Fixed | RHSA-2023:7464 |
| Red Hat Enterprise Linux BaseOS EUS (v.9.0) | Fixed | RHSA-2023:6209 |
| Red Hat Enterprise Linux BaseOS EUS (v.9.2) | Fixed | RHSA-2023:7371 |
| Red Hat Enterprise Linux Resilient Storage (v. 9) | Fixed | RHSA-2023:6744 |
| Red Hat Enterprise Linux Resilient Storage EUS (v.9.0) | Fixed | RHSA-2023:6209 |
| Red Hat Enterprise Linux Resilient Storage EUS (v.9.2) | Fixed | RHSA-2023:7371 |
| Red Hat Virtualization 4 Hypervisor for RHEL 8 | Fixed | RHSA-2023:7408 |
Timeline
- 2026-10-02 Threatist record created from CVE-2023-42669
- 2026-10-03 Alias added: GHSA-8q58-8vm2-mf3q
References
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Sources
- CVE-2023-42669 · CVE Program
- CVE-2023-42669 · NVD
- FIRST EPSS
- GHSA-8q58-8vm2-mf3q · GitHub Advisory Database · CC BY 4.0
- CVE-2023-42669 · Red Hat security data · CC BY 4.0
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