Ubuntu LinuxOperating system · Canonical
CVE-2018-16336
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 · uneditedExiv2::Internal::PngChunk::parseTXTChunk in Exiv2 v0.26 allows remote attackers to cause a denial of service (heap-based buffer over-read) via a crafted image file, a different vulnerability than CVE-2018-10999.
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 · moderate confidenceHeap-based buffer over-read vulnerability in Exiv2::Internal::PngChunk::parseTXTChunk in Exiv2 v0.26. The PNG text chunk parser fails to properly validate buffer boundaries when processing crafted image files, allowing remote attackers to trigger an out-of-bounds read leading to 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
Ubuntu LinuxOperating system
= 14.04= 16.04= 18.04= 18.10
Debian LinuxOperating system
= 8.0= 0.26CVSS 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
- Required
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/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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Confirm Exiv2 installationRun 'exiv2 -V' or 'dpkg -l | grep exiv2' (Debian/Ubuntu) to see if Exiv2 is installed and retrieve the version numberAffected if Version displayed is 0.26 exactly, or falls within the 0.26 release line (e.g., 0.26.0)
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Check Exiv2 binary version stringRun 'exiv2 --version' and examine the output for the version numberAffected if The version output shows 0.26 without a patch suffix indicating the fix (fixed in later point releases like 0.27 and later)
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Verify PNG support is enabled in Exiv2Run 'exiv2 -V | grep -i png' to confirm PNG support is compiled into the binaryAffected if PNG support is present (this is the default and required for the vulnerability to be exploitable)
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Identify PNG files processed by Exiv2Search log files, web upload directories, or image processing workflows for PNG files that may be processed by Exiv2 tools or librariesAffected if PNG files from untrusted sources are processed by Exiv2, as the vulnerability is triggered during PNG text chunk (tEXt, zTXt, iTXt) parsing
You are affected if Exiv2 version 0.26 is installed with PNG support enabled and processes PNG files from any source, since the buffer over-read occurs in the PNG text chunk parser when handling crafted files.
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 Exiv2 to a patched version; alternatively, implement strict validation and size limits on PNG files before processing with Exiv2.
Fix this in Ubuntu Linux
Scoped from the published advisory
- Consultation3.0 h
- Implementation8.0 h
- Testing6.0 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 $5,568.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2018-16336 — 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-2018-16336 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
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