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FltkApplication · Fltk Project

CVE-2021-28306

HIGH · 7.5 CVSS v3.1 Published 2021-03-12
Fix available
A fix is available. Upgrade to 0.15.3 or later.
See remediation →
84/100
Remediation priority · High
Remotely reachable No privileges Zero-click

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 · unedited
An issue was discovered in the fltk crate before 0.15.3 for Rust. There is a NULL pointer dereference during attempted use of a multi label type if the image is nonexistent.

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 confidence

The fltk crate before version 0.15.3 for Rust contains a NULL pointer dereference vulnerability. When a user attempts to use a multi-label type (Fl_Multi_Label) with a nonexistent or NULL image, the code attempts to dereference a NULL pointer, causing a crash or denial of service.

MitigationUpdate the fltk crate dependency in Cargo.toml to version 0.15.3 or later, which includes proper null validation before image pointer dereference.

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
FltkApplication
Affected:< 0.15.3

CVSS 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 checks

Work through these to decide whether this CVE applies to you.

  1. Check Cargo.toml for fltk dependency
    Look for 'fltk' or 'fltk-rs' in the [dependencies] section of your project's Cargo.toml file
    Affected if The fltk crate is listed as a dependency with a version less than 0.15.3 (e.g., 0.15.2, 0.15.1, or any 0.15.x version below 0.15.3)
  2. Check Cargo.lock for fltk version
    Search for 'name = "fltk"' in your Cargo.lock file and note the version in the corresponding [[package]] section
    Affected if The fltk crate version resolved in Cargo.lock is less than 0.15.3
  3. Inspect code for Fl_Multi_Label usage with images
    Search your source files for 'Fl_Multi_Label' and examine whether the .image() method or image parameter is used on the label
    Affected if Your code creates an Fl_Multi_Label and assigns an image that could be NULL, nonexistent, or not properly initialized

You are affected if your project depends on the fltk crate version below 0.15.3 AND your code uses Fl_Multi_Label with potentially NULL or uninitialized images.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 data
Upgrade available Upgrade to 0.15.3 or later
Fixed in 0.15.3
Interim mitigation

Update the fltk crate dependency in Cargo.toml to version 0.15.3 or later, which includes proper null validation before image pointer dereference.

Fix this in Fltk Scoped from the published advisory
  • Consultation1.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
5.0 hours of engineering $860
Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-28306 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • 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
  • No spam, self-promotion, credentials, or personal data