dbcve.org
Dns ServerApplication · Technitium

CVE-2022-30258

CRITICAL · 9.8 CVSS v3.1 Published 2022-11-21
Fix available
A fix is available. Upgrade to after 8.0.2 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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 · unedited
An issue was discovered in Technitium DNS Server through 8.0.2 that allows variant V2 of unintended domain name resolution. A revoked domain name can still be resolvable for a long time, including expired domains and taken-down malicious domains. The effects of an exploit would be widespread and highly impactful, because the exploitation conforms to de facto DNS specifications and operational practices, and overcomes current mitigation patches for "Ghost" domain names.

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 confidence

Technitium DNS Server through 8.0.2 suffers from a ghost domain variant (V2) where revoked, expired, or takedown domain names remain resolvable due to improper cache handling. This bypasses previous ghost domain mitigations, allowing malicious domains to persist in DNS resolution long after revocation.

MitigationUpdate Technitium DNS Server to a patched version beyond 8.0.2 and flush all DNS caches to remove potentially malicious cached records.

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
Dns ServerApplication
Affected:<= 8.0.2

CVSS 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
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify Technitium DNS Server version
    Check the installed version by looking at the application itself (typically displayed in the web UI header or in the About section), or check the executable file version property if installed locally.
    Affected if The installed version is 8.0.2 or any version prior to 8.0.2.
  2. Review DNS cache contents
    Access the DNS server web interface and navigate to the DNS cache section to view all cached records. Alternatively, check the cache database file if accessible on the server filesystem.
    Affected if The cache contains records for domain names that were revoked, expired, or subject to takedown but are still being served.
  3. Test resolution of known-revoked domains
    Perform DNS lookups for domain names that are known to have been revoked, expired, or formally taken down. Use tools like dig, nslookup, or the built-in DNS client in the server web interface.
    Affected if The DNS server resolves any revoked or expired domain names that should no longer be valid.
  4. Compare cache expiry times
    For cached records in the DNS cache, check the TTL (Time To Live) or expiry timestamps. Identify records where the stated expiry has passed but the domain still resolves.
    Affected if Cached records persist beyond their intended expiry time and continue resolving.

A system is affected if it runs Technitium DNS Server version 8.0.2 or earlier and its DNS cache contains or has served revoked, expired, or takedown domain names beyond their valid period.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Upgrade available Upgrade to a release after 8.0.2
Interim mitigation

Update Technitium DNS Server to a patched version beyond 8.0.2 and flush all DNS caches to remove potentially malicious cached records.

Recommended fix Moderate confidence

Technitium DNS Server 8.0.3 or later

  1. 1. Check the current installed version of Technitium DNS Server by running the DNS server software or checking its web interface
  2. 2. Download the latest stable version of Technitium DNS Server from the official GitHub releases page at github.com/TechnitiumSoftware/DnsServer
  3. 3. Back up the DNS Server configuration files and data directories before upgrading
  4. 4. Stop the Technitium DNS Server service
  5. 5. Install the latest version (8.0.3 or later)
  6. 6. Start the DNS Server service and verify it is running correctly
  7. 7. Test DNS resolution to confirm the server is functioning properly
Caveat Review release notes for any configuration or feature changes between your current version and the new version; some settings may need adjustment

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Dns Server Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,800.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2022-30258 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data