CVE-2022-30256
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 · uneditedAn issue was discovered in MaraDNS Deadwood through 3.5.0021 that allows variant V1 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 confidenceMaraDNS Deadwood through 3.5.0021 contains a ghost domain name vulnerability (variant V1) where revoked, expired, or taken-down malicious domains remain resolvable due to improper cache invalidation. The flaw bypasses existing ghost domain mitigation patches by exploiting how Deadwood handles domain name resolution and caching behavior that conforms to de facto DNS specifications.
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< 3.4.03>= 3.5.0, < 3.5.0022CVSS 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
- None
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/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 if MaraDNS Deadwood is installedCheck for the Deadwood binary or MaraDNS package. Common locations: run 'which deadwood', 'which maradns', or look for /usr/sbin/deadwood, /usr/sbin/maradns. Also check running processes with 'ps aux | grep -i deadwood' or 'ps aux | grep -i maradns'.Affected if Deadwood or MaraDNS is not found on the system (not affected). If found, proceed to version check.
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Determine installed Deadwood versionRun 'deadwood --version' or 'deadwood -v'. If using Maradns package, run 'maradns --version' or check the package version with 'dpkg -l maradns' (Debian/Ubuntu) or 'rpm -q maradns' (RHEL/CentOS).Affected if The installed version is not determined or command not found - cannot assess, seek alternative verification.
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Compare installed version against vulnerable rangesCheck if the installed version falls into: < 3.4.03 OR (>= 3.5.0 AND < 3.5.0022). Versions 3.5.0022 and later are patched. Also check if version 3.4.03 or later exists in the 3.4.x branch as a safe alternative.Affected if Installed version is < 3.4.03 OR is >= 3.5.0 but < 3.5.0022 - system is affected by the ghost domain vulnerability.
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Verify Deadwood caching is enabledExamine the Deadwood configuration file (typically dwood3rc.txt or dwood2rc in /etc/maradns/ or /etc/deadwood/). Look for 'cache_dir' or 'cache_file' settings, or inspect if Deadwood is running as a recursive resolver with caching enabled. The vulnerability only applies when caching is active.Affected if Deadwood caching is enabled (cache_dir or similar configuration present) - the ghost domain flaw can be exploited. If caching is disabled, the vulnerability may not apply.
The system is affected if Deadwood or MaraDNS is installed with a version in the ranges < 3.4.03 or >= 3.5.0 and < 3.5.0022, and caching is enabled in the configuration.
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 · scoped3.4.033.5.0022
Update Deadwood to the latest version to patch the ghost domain resolution variant, or implement additional domain revocation checking and cache invalidation mechanisms to ensure expired/revoked domains are no longer resolvable.
Upgrade to MaraDNS 3.4.03 or later (for 3.4.x branch) OR 3.5.0022 or later (for 3.5.x branch)
- 1. Identify your current MaraDNS/Deadwood version by running 'deadwood --version' or checking the package manager
- 2. Determine which version branch you are currently using (3.4.x or 3.5.x)
- 3. For systems on 3.4.x branch: upgrade to version 3.4.03 or later
- 4. For systems on 3.5.x branch: upgrade to version 3.5.0022 or later
- 5. On Debian/Ubuntu: run 'apt-get update && apt-get install maradns' or 'apt-get upgrade' to apply the fixed package
- 6. On Fedora/RHEL: run 'dnf update maradns' to apply the fixed package
- 7. Verify the new version is installed by running 'deadwood --version'
- 8. Restart the Deadwood/DNS service to load the updated binary
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation4.0 h
- Implementation8.0 h
- Testing6.0 h
- Review / QA4.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2022-30256 — 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-2022-30256 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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- 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
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