CVE-2017-5628
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 Artifex Software, Inc. MuJS before 8f62ea10a0af68e56d5c00720523ebcba13c2e6a. The MakeDay function in jsdate.c does not validate the month, leading to an integer overflow when parsing a specially crafted JS 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 confidenceMuJS JavaScript engine's MakeDay function in jsdate.c lacks month validation, allowing an untrusted month value to cause an integer overflow when parsing date values from a specially crafted JS file.
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< 2017-01-24CVSS 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
- Local
- Complexity
- Low
- Privileges
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/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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Identify if MuJS is installedCheck for the 'mujs' binary or library on the system. Common commands: which mujs, find /usr -name '*mujs*', or check package manager listings (dpkg -l | grep mujs, rpm -qa | grep mujs).Affected if The mujs binary or library is found on the system.
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Determine the installed MuJS versionRun 'mujs --version' or check the library version via 'ldd' output, package metadata, or the binary's embedded version string using 'strings' or 'file'.Affected if The version is lower than 2017-01-24 or the version cannot be determined (indicating an older build).
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Inspect the jsdate.c source file for the vulnerabilityIf the MuJS source code is accessible, locate jsdate.c and search for the MakeDay function. Verify whether month validation (typically a check ensuring month is between 0-11) is present in the function.Affected if The MakeDay function lacks bounds checking for the month parameter (no check like 'if (month < 0 || month > 11)').
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Check if date parsing from untrusted sources occursIdentify any custom JS files processed by MuJS that contain date literal or Date constructor calls (e.g., new Date(year, month, day)). Review application code that feeds files to MuJS.Affected if The environment processes untrusted or externally-sourced JS files containing date operations through MuJS.
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Verify build date of the MuJS binaryCheck the binary's modification timestamp or build metadata via 'stat mujs_binary' or review build logs if available.Affected if The binary was compiled before 2017-01-24.
The environment is affected if MuJS is installed with a version prior to 2017-01-24 AND the system processes untrusted JavaScript files containing date parsing operations.
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 data2017-01-24
Update MuJS to version containing commit 8f62ea10a0af68e56d5c00720523ebcba13c2e6a or later, which adds proper month bounds checking to prevent the integer overflow.
- Consultation1.0 h
- Implementation2.0 h
- Testing3.0 h
- Review / QA2.0 h
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Free · runs locallyCheck whether your project pulls in CVE-2017-5628 — 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-2017-5628 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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