CVE-2020-24696
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 PowerDNS Authoritative through 4.3.0 when --enable-experimental-gss-tsig is used. A remote, unauthenticated attacker can trigger a race condition leading to a crash, or possibly arbitrary code execution, by sending crafted queries with a GSS-TSIG signature.
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 · high confidencePowerDNS Authoritative Server versions through 4.3.0 contain a race condition vulnerability in the experimental GSS-TSIG implementation. When the --enable-experimental-gss-tsig build flag is used, a remote unauthenticated attacker can send specially crafted queries with GSS-TSIG signatures to trigger the race condition, causing a denial of service (crash) or potentially achieving arbitrary code execution on the server.
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<= 4.3.0CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:H/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 checksWork through these to decide whether this CVE applies to you.
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Check if GSS-TSIG was compiled into the binaryRun 'pdns --version' and look for GSS/TSIG in the output. On Linux you can also run 'strings $(which pdns) | grep -i gss-tsig' to search the binary for GSS-TSIG related strings.Affected if The binary shows GSS-TSIG support was compiled in (the build included --enable-experimental-gss-tsig)
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Determine installed PowerDNS versionRun 'pdns --version' and note the version number displayed.Affected if The version is 4.3.0 or lower (any version up to and including 4.3.0)
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Check if GSS-TSIG is enabled in configurationExamine pdns.conf (typically /etc/pdns/pdns.conf or /etc/powerdns/pdns.conf) for lines containing 'gss' or 'tsig' keywords.Affected if GSS-TSIG is explicitly enabled or configured in the configuration file
You are affected if PowerDNS version is 4.3.0 or lower AND the binary was compiled with --enable-experimental-gss-tsig AND GSS-TSIG is in use.
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.
From vendor dataDisable the experimental GSS-TSIG feature if enabled (rebuild without --enable-experimental-gss-tsig), or upgrade to PowerDNS Authoritative 4.3.1 or later which contains the fix for this vulnerability.
- Consultation4.0 h
- Implementation2.0 h
- Testing4.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-24696 — 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-2020-24696 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
- No spam, self-promotion, credentials, or personal data