FedoraOperating system · Fedoraproject
CVE-2021-42384
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 · uneditedA use-after-free in Busybox's awk applet leads to denial of service and possibly code execution when processing a crafted awk pattern in the handle_special function
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 confidenceA use-after-free vulnerability in BusyBox's awk applet (handle_special function) allows memory corruption when processing a crafted awk pattern, potentially enabling denial of service or arbitrary 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
FedoraOperating system
= 33= 34>= 1.18.0, <= 1.33.1CVSS 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
- High
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:H/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 installed BusyBox versionRun 'busybox --version' or 'busybox | head -1' to display the version stringAffected if Version is between 1.18.0 and 1.33.1 inclusive
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Confirm BusyBox awk applet is availableRun 'busybox --list | grep awk' or 'which awk' to verify the awk applet is included in the buildAffected if The awk command is available and linked to BusyBox
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Verify Fedora distribution versionCheck /etc/fedora-release or run 'cat /etc/os-release' to identify the Fedora versionAffected if Running Fedora 33 or Fedora 34 with the affected BusyBox version
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Check if awk is the BusyBox implementationRun 'ls -la $(which awk)' to see if awk is a symlink to BusyBox or run 'awk --version' to identify the implementationAffected if The awk utility resolves to BusyBox's awk applet
You are affected if BusyBox version 1.18.0 to 1.33.1 is installed with the awk applet enabled, particularly on Fedora 33 or 34.
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 · scopedUpdate BusyBox to a version containing the security fix; audit systems using BusyBox's awk functionality for potential exploitation vectors.
Busybox >= 1.33.2 (or latest stable 1.34.x/1.35.x release)
- Identify the current Busybox version installed on the system using 'busybox --version' or 'rpm -q busybox'
- For Fedora systems: Run 'sudo dnf update busybox' to apply the latest available package which includes the security fix
- For other systems: Obtain and install Busybox version 1.33.2 or later from the official Busybox project or your distribution's package repositories
- Verify the updated version using 'busybox --version' to confirm the fix is applied
- Test the awk functionality to ensure the applet works correctly after the update
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Fedora
Scoped from the published advisory
- Consultation6.0 h
- Implementation3.0 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 $4,848.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-42384 — 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-2021-42384 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
- No spam, self-promotion, credentials, or personal data