CVE-2026-33609
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIncomplete escaping of LDAP queries when running with 8bit-dns enabled allows users to perform queries of internal domain subtrees.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · moderate confidenceIncomplete escaping of LDAP queries when the 8bit-dns configuration option is enabled allows authenticated users to perform queries of internal domain subtrees they should not have access to. This is an LDAP injection vulnerability combined with improper authorization boundaries.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 4.9.0, < 4.9.14>= 5.0.0, < 5.0.4CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify Powerdns Authoritative versionRun 'pdns --version' or check the package manager (dpkg -l pdns-auth, rpm -q pdns-auth) to determine the installed versionAffected if Version is >= 4.9.0 and < 4.9.14, or >= 5.0.0 and < 5.0.4
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Confirm LDAP backend is in useInspect the Powerdns configuration file (typically /etc/pdns/pdns.conf or /etc/powerdns/pdns.conf) for 'launch' or 'backend' settings containing 'ldap'Affected if An LDAP backend is configured in the launch directive
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Verify 8bit-dns option is enabledSearch the Powerdns configuration file for '8bit-dns' setting and confirm it is set to 'yes' or 'true'Affected if 8bit-dns is explicitly enabled in the configuration
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Check LDAP query configurationReview the LDAP-related configuration parameters in pdns.conf (such as ldap-host, ldap-base-dn, ldap-filter) to identify where user input flows into LDAP search filtersAffected if LDAP backend is configured with filters that incorporate user-supplied domain names without proper escaping
A user is affected if they run a vulnerable Powerdns Authoritative version (4.9.0-4.9.13 or 5.0.0-5.0.3) with the LDAP backend and the 8bit-dns option enabled.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped4.9.145.0.4
Implement proper LDAP query escaping/parameterization for all user-controlled input and review the necessity of the 8bit-dns setting; disable it if not required, or ensure all query parameters are strictly validated before being incorporated into LDAP search filters.
4.9.14 or 5.0.4 (depending on your current major version branch)
- 1. Identify your current PowerDNS Authoritative Server version using 'pdns --version'
- 2. If running 4.9.x (>=4.9.0, <4.9.14): Upgrade to version 4.9.14
- 3. If running 5.0.x (>=5.0.0, <5.0.4): Upgrade to version 5.0.4
- 4. Consult PowerDNS upgrade documentation at docs.powerdns.com for your specific version transition
- 5. After upgrade, verify the fix by testing LDAP-backed domain queries with 8bit-dns enabled
- 6. Ensure LDAP query parameters are properly escaped in your configuration
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation4.0 h
- Testing3.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-33609 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-33609 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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