Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD.
CVSS VectorNVD
Lifecycle Timeline
7DescriptionNVD
An attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code. In some cases the rewritten packet might become larger than the initial response and even exceed 65535 bytes, potentially leading to a crash resulting in denial of service.
AnalysisAI
DNSdist fails to validate packet size bounds when rewriting DNS questions or responses via Lua methods (DNSQuestion:changeName, DNSResponse:changeName), allowing unauthenticated remote attackers to craft DNS responses that trigger out-of-bounds writes and exceed the 65535-byte DNS packet size limit, resulting in denial of service via crash. CVSS 5.9 (high availability impact); no public exploit code identified at time of analysis.
Technical ContextAI
DNSdist is a high-performance DNS load balancer and distribution tool that supports custom packet manipulation via embedded Lua scripting. The vulnerability resides in the Lua API methods DNSQuestion:changeName and DNSResponse:changeName, which allow dynamic rewriting of DNS names within packets. The root cause is insufficient bounds checking: when a name rewrite operation expands the packet payload (e.g., replacing a short label with a longer one), the implementation does not validate that the resulting packet remains within the DNS protocol limit of 65535 bytes. This can lead to a buffer overflow condition when the packet is serialized and transmitted. The affected product is DNSdist across all versions using these Lua methods without proper size validation (cpe:2.3:a:powerdns:dnsdist:*:*:*:*:*:*:*:*).
RemediationAI
Apply the vendor-released patch from PowerDNS for DNSdist that adds proper packet size validation to the DNSQuestion:changeName and DNSResponse:changeName Lua methods. Detailed patched versions and upgrade instructions are available in the official security advisory at https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-02.html. As an interim mitigation, disable or restrict custom Lua rules that use DNSQuestion:changeName or DNSResponse:changeName methods until patched, or implement external validation to ensure rewritten DNS packets do not exceed 65535 bytes. Organizations should review their DNSdist configurations to identify whether these Lua methods are in use; default configurations without custom code are not affected.
dnsdist version 1.1.0 is vulnerable to a flaw in authentication mechanism for REST API potentially allowing CSRF attack.
Out-of-bounds read in PowerDNS dnsdist allows unauthenticated remote attackers to trigger denial of service or potential
Remote denial of service in dnsdist allows unauthenticated attackers to crash the DNS load balancer by sending specially
Memory exhaustion in DNSdist allows remote, unauthenticated attackers to trigger denial of service by crafting malicious
DNSdist instances using custom Lua code can be crashed via denial of service when the DNSQuestion:getEDNSOptions method
DNSdist is vulnerable to denial of service via out-of-bounds write when processing crafted UDP responses from a rogue ba
PowerDNS dnsdist allows unauthenticated DNS over HTTPS (DoH) queries to bypass access control lists when the early_acl_d
An issue has been found in PowerDNS DNSDist before 1.3.3 allowing a remote attacker to craft a DNS query with trailing d
Denial of service in PowerDNS Authoritative, Recursor, and dnsdist via unbounded memory allocation in their internal web
Unlimited memory allocation in PowerDNS internal web server allows remote denial of service via crafted web requests. Th
dnsdist allows remote denial-of-service attacks through memory exhaustion by generating numerous error responses on sing
dnsdist can be forced into excessive memory allocation when a client generates high volumes of DNS queries routed to an
Same weakness CWE-787 – Out-of-bounds Write
View allSame technique Buffer Overflow
View allVendor StatusVendor
Debian
| Release | Status | Fixed Version | Urgency |
|---|---|---|---|
| bullseye | fixed | (unfixed) | end-of-life |
| bookworm | fixed | (unfixed) | end-of-life |
| trixie | vulnerable | 1.9.10-1+deb13u1 | - |
| forky | vulnerable | 2.0.2-1 | - |
| sid | fixed | 2.0.3-1 | - |
| (unstable) | fixed | 2.0.3-1 | - |
SUSE
Severity: Medium| Product | Status |
|---|---|
| SUSE Linux Enterprise Desktop 15 SP7 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 15 SP7 | Fixed |
| SUSE Linux Enterprise Server 16.0 | Fixed |
| SUSE Linux Enterprise Server 16.1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Fixed |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Fixed |
| openSUSE Leap 15.6 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | Fixed |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP5 | Fixed |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP6 | Fixed |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Fixed |
| SUSE Manager Proxy 4.3 | Fixed |
| SUSE Manager Proxy LTS 4.3 | Fixed |
| SUSE Manager Retail Branch Server 4.3 | Fixed |
| SUSE Manager Retail Branch Server LTS 4.3 | Fixed |
| SUSE Manager Server 4.3 | Fixed |
| SUSE Manager Server LTS 4.3 | Fixed |
| SUSE CaaS Platform 4.0 | Fixed |
| SUSE Enterprise Storage 7.1 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP4 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP5 | Fixed |
| SUSE Linux Enterprise Desktop 15 SP6 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Fixed |
| SUSE Linux Enterprise Real Time 15 SP4 | Fixed |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Fixed |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Fixed |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Fixed |
| openSUSE Leap 15.4 | Fixed |
| openSUSE Leap 15.5 | Fixed |
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-17407
GHSA-w68q-j3pw-29rg