NginxWeb server / proxy · F5
CVE-2018-16844
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 · uneditednginx before versions 1.15.6 and 1.14.1 has a vulnerability in the implementation of HTTP/2 that can allow for excessive CPU usage. This issue affects nginx compiled with the ngx_http_v2_module (not compiled by default) if the 'http2' option of the 'listen' directive is used in a configuration file.
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 confidencenginx contains a denial-of-service vulnerability in its HTTP/2 implementation that allows excessive CPU consumption. The issue only affects nginx instances compiled with the ngx_http_v2_module (not compiled by default) where the 'http2' option is explicitly enabled on a 'listen' directive in the configuration.
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
NginxWeb server / proxy
>= 1.9.5, < 1.14.1>= 1.15.0, < 1.15.6
Debian LinuxOperating system
= 9.0
Ubuntu LinuxOperating system
= 14.04= 16.04= 18.04= 18.10< 13.0CVSS 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
- Low
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 nginx versionRun 'nginx -v' or 'nginx -V' to see the installed versionAffected if Version is >= 1.9.5 and < 1.14.1, or >= 1.15.0 and < 1.15.6
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Verify ngx_http_v2_module is compiledRun 'nginx -V 2>&1 | grep -o http_v2_module' to see if the module is compiled inAffected if The http_v2_module appears in the output, indicating it is compiled into the binary
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Check for http2 enabled on listen directivesInspect nginx configuration files (typically in /etc/nginx/) and search for 'listen' directives with the 'http2' option, such as 'listen 443 http2;'Affected if Any 'listen' directive explicitly includes the 'http2' parameter
You are affected if nginx is running a vulnerable version (1.9.5 to 1.14.0 or 1.15.0 to 1.15.5), was compiled with the http_v2 module, AND has http2 enabled on any listen directive 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.
From vendor data1.14.11.15.613.0
Upgrade nginx to version 1.15.6, 1.14.1, or later. If upgrading is not immediately feasible, disable the http2 option on listen directives or ensure the ngx_http_v2_module is not compiled into the binary.
Fix this in Nginx
Scoped from the published advisory
- Consultation2.0 h
- Implementation2.0 h
- Testing2.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-16844 — 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-2018-16844 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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