CVE-2026-45740
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 · uneditedprotobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.8 and 8.2.0, protobufjs could recurse without a depth limit while expanding nested JSON descriptors through Root.fromJSON() and Namespace.addJSON(). A crafted JSON descriptor with deeply nested namespace definitions could cause the JavaScript call stack to be exhausted during descriptor loading. This vulnerability is fixed in 7.5.8 and 8.2.0.
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 confidenceprotobufjs had an unbounded recursion vulnerability in Root.fromJSON() and Namespace.addJSON() when expanding nested JSON descriptors. A maliciously crafted JSON descriptor with deeply nested namespace definitions could exhaust the JavaScript call stack, causing a denial of service.
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< 7.5.8>= 8.0.0, < 8.2.0CVSS 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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Identify protobufjs installationRun 'npm list protobufjs' or check your package.json dependencies for protobufjsAffected if protobufjs is not listed as a dependency in your project
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Determine installed versionRun 'npm list protobufjs --depth=0' to see the exact version installed, or check package-lock.json for the protobufjs version entryAffected if The installed version is less than 7.5.8, or greater than or equal to 8.0.0 but less than 8.2.0
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Check for usage of fromJSON or addJSONSearch your codebase for calls to Root.fromJSON() or Namespace.addJSON() method invocationsAffected if Your code calls either method with JSON input from untrusted or external sources
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Inspect input source to fromJSON or addJSONReview the code paths that feed data into fromJSON() or addJSON() to determine if the JSON could originate from user input, API responses, or untrusted filesAffected if Untrusted or user-controlled JSON is passed to these methods without pre-validation of nesting depth
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Assess JSON nesting depthIf fromJSON() or addJSON() is used, trace back to the JSON source and evaluate or estimate the maximum depth of nested objects or namespace definitions in that dataAffected if The JSON data could contain deeply nested structures (dozens or hundreds of levels) without depth limits being enforced beforehand
Your environment is affected if protobufjs version is less than 7.5.8 or between 8.0.0 and 8.2.0 exclusive AND your code passes untrusted or deeply nested JSON to Root.fromJSON() or Namespace.addJSON().
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 · scoped7.5.88.2.0
Upgrade protobufjs to version 7.5.8 or 8.2.0 or later. If immediate upgrade is not feasible, validate and limit the nesting depth of JSON descriptors before passing them to fromJSON() or addJSON().
protobufjs 7.5.8 or higher (7.x branch), or protobufjs 8.2.0 or higher (8.x branch)
- Check the current version of protobufjs in use by examining package.json or running 'npm list protobufjs'
- Upgrade to protobufjs version 7.5.8 or higher for the 7.x branch, or version 8.2.0 or higher for the 8.x branch
- Run 'npm update protobufjs' or 'npm install protobufjs@<fixed_version>' to apply the upgrade
- Verify the upgrade was successful by running 'npm list protobufjs' to confirm the installed version
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation4.0 h
- Testing5.0 h
- Review / QA3.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,176.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-45740 — 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-2026-45740 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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