Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Remote unauthenticated crafted query (AV:N/AC:L/PR:N/UI:N); primary impacts are daemon crash (A:H) and RPZ filtering bypass (I:L), with no data disclosure (C:N).
Primary rating from Vendor (isc).
CVSS VectorVendor: isc
Lifecycle Timeline
2DescriptionCVE.org
An attacker who knows (or guesses) that a resolver uses RPZ with wildcard CNAME policies can craft query names long enough to trigger a NAMETOOLONG error condition during RPZ processing. This is not handled correctly and may lead to defeating the RPZ rule. It also may lead to an unexpected exit of the BIND 9 software. This issue affects BIND 9 versions 9.16.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.16.8-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
AnalysisAI
RPZ policy bypass and remote denial-of-service in ISC BIND 9 resolvers lets unauthenticated attackers defeat Response Policy Zone protections or crash the daemon by sending queries with names long enough to trigger a NAMETOOLONG condition during RPZ processing. Affected are BIND 9.16.0-9.18.50, 9.20.0-9.20.24, 9.21.0-9.21.23 and the corresponding -S (subscription) editions, but only where RPZ is configured with wildcard CNAME policies. No public exploit identified at time of analysis; the vendor (ISC) has released fixed builds 9.20.26 and 9.21.24.
Technical ContextAI
BIND 9 is the reference implementation of DNS and one of the most widely used recursive resolver/authoritative servers (cpe:2.3:a:isc:bind_9). Response Policy Zones (RPZ) are a DNS firewall mechanism that let operators rewrite or block answers for malicious domains; wildcard CNAME policies (e.g. *.evil.example CNAME rpz-drop) apply an action across a whole subtree. The flaw is classed as CWE-790 (Improper Filtering of Special Elements): during RPZ evaluation, constructing the synthesized/expanded name from an attacker-supplied very long query name overruns the DNS 255-octet name limit and raises a NAMETOOLONG error that the RPZ code path does not handle correctly. The mishandling either aborts RPZ evaluation before the policy is applied (bypass) or propagates into an assertion/unexpected termination of the named process.
RemediationAI
Vendor-released patch: upgrade to BIND 9.20.26 (https://downloads.isc.org/isc/bind9/9.20.26) or 9.21.24 (https://downloads.isc.org/isc/bind9/9.21.24), per ISC advisory https://kb.isc.org/docs/cve-2026-11331; subscription-edition users should obtain the equivalent -S build from ISC support. If patching cannot be done immediately, the most direct compensating control is to remove or rewrite wildcard CNAME entries in RPZ policy zones (replacing wildcard CNAME actions with explicit per-name policies or non-CNAME actions such as CNAME rpz-drop/rpz-passthru on specific labels), which eliminates the vulnerable code path at the cost of coarser policy coverage; alternatively, temporarily disabling RPZ (response-policy) removes the exposure entirely but also removes DNS-firewall protection, so weigh that trade-off. Restrict recursive service to trusted clients via allow-query/allow-recursion ACLs to limit who can send the crafted queries.
BIND resolver servers performing DNSSEC validation can be forced into excessive CPU consumption when encountering a mali
Memory exhaustion in BIND 9 resolver allows unauthenticated remote attackers to cause denial of service by querying spec
Memory corruption in ISC BIND 9's DNS-over-HTTPS (DoH) implementation lets remote attackers trigger a use-after-free (CW
DNSSEC validation bypass in ISC BIND 9 resolvers (9.11.0 through 9.21.23 and S-editions) allows an attacker controlling
Denial of service in ISC BIND 9 lets a remote unauthenticated attacker exhaust resolver memory by flooding a DNSSEC-vali
Remote denial of service in ISC BIND 9 lets an attacker crash a validating resolver via a maliciously crafted DNSSEC pro
Denial of service in ISC BIND 9 resolvers (9.20.0-9.20.24, 9.21.0-9.21.23, and 9.20.9-S1-9.20.24-S1) lets remote unauthe
Cache poisoning in ISC BIND 9 recursive resolvers allows an attacker who controls an authoritative zone to inject forged
Remote denial of service in ISC BIND 9 lets an off-path attacker crash a recursive resolver by controlling the timing an
Denial of service in ISC BIND 9 DNS servers configured with TKEY GSS-API authentication allows remote unauthenticated at
Remote denial of service in ISC BIND 9 named allows unauthenticated attackers to trigger assertion failures and crash th
DNSSEC integrity bypass in ISC BIND 9 enables network-positioned attackers to forge authenticated NXDOMAIN responses by
Same weakness CWE-790 – Improper Filtering of Special Elements
View allSame technique Information Disclosure
View allVendor StatusVendor
SUSE
Severity: Important| Product | Status |
|---|---|
| SUSE Linux Enterprise Desktop 15 SP7 SUSE Linux Enterprise Module for Basesystem 15 SP7 | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP7 SUSE Linux Enterprise Server 15 SP7 SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Fixed |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | Fixed |
| openSUSE Leap 16.0 | Fixed |
| openSUSE Tumbleweed | Fixed |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Micro 5.5 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE Linux Enterprise Desktop 15 SP7 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Micro 5.5 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server 16.1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Affected |
| SUSE Manager Client Tools for SLE Micro 5 | Affected |
| SUSE Multi-Linux Manager Client Tools for SLE Micro 5 | Affected |
| SUSE Linux Enterprise High Performance Computing 12 SP5 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP4 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP5 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP6 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server 12 SP5 | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 12 SP5-LTSS Extended Security | Affected |
| SUSE Linux Enterprise Server 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5 | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP5 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Manager Proxy 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE CaaS Platform 3.0 | Not-Affected |
| SUSE CaaS Platform 4.0 | Affected |
| SUSE Enterprise Storage 6 | Affected |
| SUSE Enterprise Storage 7 | Affected |
| SUSE Enterprise Storage 7.1 | Affected |
| SUSE Linux Enterprise Desktop 12 SP1 | Not-Affected |
| SUSE Linux Enterprise Desktop 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Desktop 12 SP3 | Not-Affected |
| SUSE Linux Enterprise Desktop 12 SP4 | Affected |
| SUSE Linux Enterprise Desktop 15 | Affected |
| SUSE Linux Enterprise Desktop 15 SP1 | Affected |
| SUSE Linux Enterprise Desktop 15 SP2 | Affected |
| SUSE Linux Enterprise Desktop 15 SP3 | Affected |
| SUSE Linux Enterprise Desktop 15 SP4 | Affected |
| SUSE Linux Enterprise Desktop 15 SP5 | Affected |
| SUSE Linux Enterprise Desktop 15 SP6 | Affected |
| SUSE Linux Enterprise High Performance Computing 12 SP1 | Not-Affected |
| SUSE Linux Enterprise High Performance Computing 12 SP2 | Not-Affected |
| SUSE Linux Enterprise High Performance Computing 12 SP3 | Not-Affected |
| SUSE Linux Enterprise High Performance Computing 12 SP4 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Affected |
| SUSE Linux Enterprise High Performance Computing 15-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15-LTSS | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP1 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Basesystem 15 SP3 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Point of Sale 12 SP2-CLIENT | Not-Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | Affected |
| SUSE Linux Enterprise Server 12 SP1 | Not-Affected |
| SUSE Linux Enterprise Server 12 SP1-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2-BCL | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2-ESPOS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP2-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3 | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3-BCL | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3-ESPOS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP3-LTSS | Not-Affected |
| SUSE Linux Enterprise Server 12 SP4 | Affected |
| SUSE Linux Enterprise Server 12 SP4-ESPOS | Affected |
| SUSE Linux Enterprise Server 12 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 | Affected |
| SUSE Linux Enterprise Server 15 SP1 | Affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP2 | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP3 | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise Server 15-LTSS | Affected |
| SUSE Linux Enterprise Server for Raspberry Pi 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP1 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP3 | Not-Affected |
| SUSE Linux Enterprise Server for SAP Applications 12 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Software Development Kit 12 SP1 | Not-Affected |
| SUSE Linux Enterprise Software Development Kit 12 SP2 | Not-Affected |
| SUSE Linux Enterprise Software Development Kit 12 SP3 | Not-Affected |
| SUSE Linux Enterprise Software Development Kit 12 SP4 | Affected |
| SUSE Linux Enterprise Software Development Kit 12 SP5 | Affected |
| SUSE Manager Proxy 4.0 | Affected |
| SUSE Manager Proxy 4.1 | Affected |
| SUSE Manager Proxy 4.2 | Affected |
| SUSE Manager Retail Branch Server 4.0 | Affected |
| SUSE Manager Retail Branch Server 4.1 | Affected |
| SUSE Manager Retail Branch Server 4.2 | Affected |
| SUSE Manager Server 4.0 | Affected |
| SUSE Manager Server 4.1 | Affected |
| SUSE Manager Server 4.2 | Affected |
| SUSE OpenStack Cloud 7 | Not-Affected |
| SUSE OpenStack Cloud 8 | Not-Affected |
| SUSE OpenStack Cloud 9 | Affected |
| SUSE OpenStack Cloud Crowbar 8 | Not-Affected |
| SUSE OpenStack Cloud Crowbar 9 | Affected |
| openSUSE Leap 15.3 | Affected |
| openSUSE Leap 15.4 | Affected |
| openSUSE Leap 15.5 | Affected |
| openSUSE Leap 15.6 | Affected |
| SUSE Multi Linux Manager Tools Beta SLE-Micro-5 | Affected |
| SUSE Multi Linux Manager Tools SLE-Micro-5 | Affected |
| suse/bind | Affected |
| suse/bind:9 | Affected |
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-47706
GHSA-8p39-mp4q-99c8