CVE-2018-11576
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 · uneditedngiflib.c in MiniUPnP ngiflib 0.4 has a heap-based buffer over-read in GifIndexToTrueColor.
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 confidenceHeap-based buffer over-read vulnerability in ngiflib 0.4's GifIndexToTrueColor function allows reading memory beyond allocated buffer boundaries when processing GIF image data. This memory safety issue in the GIF parsing logic could allow attackers to read sensitive heap contents or potentially achieve code execution.
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= 0.4CVSS 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
- High
- Integrity
- High
- Availability
- High
CVSS:3.0/AV:N/AC:L/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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Identify ngiflib versionSearch for version.h, ngiflib.h, or similar header files in the codebase; check for version constants like #define NGIFLIB_VERSION "0.4" or version strings in compiled library binariesAffected if The version is 0.4 or the version cannot be determined (unknown versions should be treated as potentially vulnerable)
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Locate the GifIndexToTrueColor functionSearch source code for 'GifIndexToTrueColor' function definition; if using a compiled library, check for this symbol in the binary using tools like nm, objdump, or stringsAffected if The function exists in the codebase or linked library, indicating the vulnerable code is present
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Determine if GIF decoding is performedSearch for GIF loading/parsing code paths: look for calls to functions like GifDecode, GifLoad, or any code that processes .gif files or GIF data streamsAffected if The application or library decodes or parses GIF images, which would invoke the vulnerable function
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Check if the vulnerable function is actually calledTrace code paths from GIF loading to GifIndexToTrueColor; verify if color index to true color conversion occurs during normal GIF processing (this is typically a standard step in GIF decoding)Affected if GIF files are processed, which by design calls GifIndexToTrueColor to convert color indices to actual RGB values from the color table
You are affected if ngiflib version 0.4 is in use AND your application or library processes GIF image data, as this triggers the vulnerable GifIndexToTrueColor function.
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 dataUpgrade to a patched version of ngiflib; if no patch available, implement bounds checking in GifIndexToTrueColor to validate color table indices before accessing array elements.
- Consultation3.0 h
- Implementation6.0 h
- Testing5.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,464.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-11576 — 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-2018-11576 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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