Upstream information
Description
In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, client terminated DNS-over-QUIC (DoQ) queries are not accounted properly by Unbound resulting in low-cost inflation of the waiting number of replies for already in-flight resolution queries. This results in degradation of resolution service for new clients for already in-flight queries. A malicious actor can exploit the vulnerability by issuing DoQ queries for query names that need resolution and proceeding on immediately terminating the query by one of STOP_SENDING/RESET_STREAM/CONNECTION_CLOSE QUIC frames. Those terminated DoQ queries are not properly counted for and keep inflating the number of waiting replies for in-flight queries. When the maximum is reached, it results in silent query drops for new clients needing resolution for already in-flight queries. This vulnerability needs Unbound to be compiled with DoQ support ('--with-libngtcp2') and the 'quic-port' to be configured for the listening interfaces. Additionally, a malicious actor needs access to multiple source IPs to bypass the by-default configured 'wait-limit' option.SUSE information
Overall state of this security issue: Pending
This issue is currently rated as having moderate severity.
| CVSS detail | CNA (NLnet Labs) | SUSE |
|---|---|---|
| Base Score | 3.7 | 3.7 |
| Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L |
| Attack Vector | Network | Network |
| Attack Complexity | High | High |
| Privileges Required | None | None |
| User Interaction | None | None |
| Scope | Unchanged | Unchanged |
| Confidentiality Impact | None | None |
| Integrity Impact | None | None |
| Availability Impact | Low | Low |
| CVSSv3 Version | 3.1 | 3.1 |
| CVSS detail | SUSE |
|---|---|
| Base Score | 6.3 |
| Vector | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N |
| Attack Vector | Network |
| Attack Complexity | Low |
| Attack Requirements | Present |
| Privileges Required | None |
| User Interaction | None |
| Vulnerable System Confidentiality Impact | None |
| Vulnerable System Integrity Impact | None |
| Vulnerable System Availability Impact | Low |
| Subsequent System Confidentiality Impact | None |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
SUSE Security Advisories:
- SUSE-SU-2026:23050-1, published 2026-08-10T15:26:22Z
- SUSE-SU-2026:23215-1, published 2026-08-10T15:26:22Z
- SUSE-SU-2026:23226-1, published 2026-08-10T15:27:28Z
List of released packages
| Product(s) | Fixed package version(s) | References |
|---|---|---|
| SUSE Linux Enterprise Server 16.0 SUSE Linux Enterprise Server for SAP applications 16.0 |
| Patchnames: SUSE-SLES-16.0-1446 (aarch64,ppc64le,s390x,x86_64) |
| SUSE Linux Micro 6.0 |
| Patchnames: SUSE-SLE-Micro-6.0-864 (aarch64,s390x,x86_64) |
| SUSE Linux Micro 6.1 |
| Patchnames: SUSE-SLE-Micro-6.1-686 (aarch64,ppc64le,s390x,x86_64) |
| SUSE Linux Micro 6.2 |
| Patchnames: SUSE-SL-Micro-6.2-1446 (aarch64,ppc64le,s390x,x86_64) |
| openSUSE Leap 16.0 |
| Patchnames: openSUSE-Leap-16.0-1446 |
| openSUSE Tumbleweed |
| Patchnames: openSUSE-Tumbleweed-2026-11380 |
Status of this issue by product and package
Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.
| Product(s) | Source package | State |
|---|---|---|
| Products under general support and receiving all security fixes. | ||
| SUSE Linux Enterprise Desktop 15 SP7 | unbound | Not affected |
| SUSE Linux Enterprise Micro 5.5 | unbound | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | unbound | Not affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP7 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP7 | unbound | Not affected |
| SUSE Linux Enterprise Server 16.0 | unbound | Released |
| SUSE Linux Enterprise Server 16.1 | unbound | Released |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | unbound | Not affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | unbound | Released |
| SUSE Linux Enterprise Server for SAP applications 16.1 | unbound | Released |
| SUSE Linux Micro 6.0 | unbound | Released |
| SUSE Linux Micro 6.1 | unbound | Released |
| SUSE Linux Micro 6.2 | unbound | Released |
| openSUSE Leap 16.0 | unbound | Affected |
| Products under Long Term Service Pack support and receiving important and critical security fixes. | ||
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | unbound | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | unbound | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | unbound | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP4 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP5 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP6 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | unbound | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | unbound | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | unbound | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | unbound | Not affected |
| Products past their end of life and not receiving proactive updates anymore. | ||
| SUSE CaaS Platform 4.0 | unbound | Not affected |
| SUSE Enterprise Storage 6 | unbound | Not affected |
| SUSE Enterprise Storage 7 | unbound | Not affected |
| SUSE Enterprise Storage 7.1 | unbound | Not affected |
| SUSE Linux Enterprise Desktop 15 SP1 | unbound | Not affected |
| SUSE Linux Enterprise Desktop 15 SP2 | unbound | Not affected |
| SUSE Linux Enterprise Desktop 15 SP3 | unbound | Not affected |
| SUSE Linux Enterprise Desktop 15 SP4 | unbound | Not affected |
| SUSE Linux Enterprise Desktop 15 SP5 | unbound | Not affected |
| SUSE Linux Enterprise Desktop 15 SP6 | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | unbound | Not affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | unbound | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP1 | unbound | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP2 | unbound | Not affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | unbound | Not affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP3 | unbound | Not affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP4 | unbound | Not affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP5 | unbound | Not affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP6 | unbound | Not affected |
| SUSE Linux Enterprise Real Time 15 SP2 | unbound | Not affected |
| SUSE Linux Enterprise Real Time 15 SP3 | unbound | Not affected |
| SUSE Linux Enterprise Real Time 15 SP4 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP1 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP2 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP3 | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | unbound | Not affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | unbound | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | unbound | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | unbound | Not affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | unbound | Not affected |
| SUSE Manager Proxy 4.0 | unbound | Not affected |
| SUSE Manager Proxy 4.1 | unbound | Not affected |
| SUSE Manager Proxy 4.2 | unbound | Not affected |
| SUSE Manager Proxy 4.3 | unbound | Not affected |
| SUSE Manager Proxy LTS 4.3 | unbound | Not affected |
| SUSE Manager Retail Branch Server 4.0 | unbound | Not affected |
| SUSE Manager Retail Branch Server 4.1 | unbound | Not affected |
| SUSE Manager Retail Branch Server 4.2 | unbound | Not affected |
| SUSE Manager Retail Branch Server 4.3 | unbound | Not affected |
| SUSE Manager Retail Branch Server LTS 4.3 | unbound | Not affected |
| SUSE Manager Server 4.0 | unbound | Not affected |
| SUSE Manager Server 4.1 | unbound | Not affected |
| SUSE Manager Server 4.2 | unbound | Not affected |
| SUSE Manager Server 4.3 | unbound | Not affected |
| SUSE Manager Server LTS 4.3 | unbound | Not affected |
| openSUSE Leap 15.3 | unbound | Not affected |
| openSUSE Leap 15.4 | unbound | Not affected |
| openSUSE Leap 15.5 | unbound | Not affected |
| openSUSE Leap 15.6 | unbound | Not affected |
SUSE Timeline for this CVE
CVE page created: Thu Jul 23 11:34:34 2026CVE page last modified: Tue Sep 1 11:33:42 2026