WhatsappApplication

CVE-2021-24035

CRITICAL · 9.1 CVSS v3.1 Published 2021-06-11

Fix available

A fix is available. Upgrade to 2.21.8.13 or later.

See remediation →

100/100

Remediation priority · Urgent

Remotely reachable No privileges Zero-click

Official description

NVD · unedited

A lack of filename validation when unzipping archives prior to WhatsApp for Android v2.21.8.13 and WhatsApp Business for Android v2.21.8.13 could have allowed path traversal attacks that overwrite WhatsApp files.

Technical summary

dbcve analysis · high confidence

Path traversal vulnerability in WhatsApp for Android and WhatsApp Business for Android's archive extraction functionality. The application fails to validate filenames during unzip operations, allowing attackers to use '..' sequences in malicious zip archives to write files outside the intended directory and overwrite WhatsApp application files.

MitigationUpdate WhatsApp for Android and WhatsApp Business for Android to version v2.21.8.13 or later to obtain the patched application with proper filename validation.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions

NVD · CPE data

WhatsappApplication

Affected:< 2.21.8.13

Whatsapp BusinessApplication

Affected:< 2.21.8.13

CVSS breakdown

From the vector

Attack vector: Network
Complexity: Low
Privileges: None
User interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: High
Availability: High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

Am I affected?

dbcve checks

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

Identify installed WhatsApp application

Go to Settings > Apps on the Android device and check if WhatsApp or WhatsApp Business for Android is installed. Note the exact package name listed (com.whatsapp or com.whatsapp.w4b).

Affected if Either WhatsApp or WhatsApp Business for Android is present on the device
Check WhatsApp version number

Open WhatsApp, tap the three-dot menu > Settings > Help > App info. Alternatively, go to Settings > Apps > WhatsApp and view the Version field under App information.

Affected if The displayed version number is lower than 2.21.8.13
Check WhatsApp Business version number

Open WhatsApp Business, tap the three-dot menu > Settings > Help > App info. Alternatively, go to Settings > Apps > WhatsApp Business and view the Version field under App information.

Affected if The displayed version number is lower than 2.21.8.13
Verify version via ADB (optional)

If ADB is available, run: adb shell dumpsys package com.whatsapp (or com.whatsapp.w4b) and locate the versionName field in the output.

Affected if The versionName field shows a value less than 2.21.8.13

The device is affected if WhatsApp or WhatsApp Business for Android is installed with any version lower than 2.21.8.13, as the vulnerability exists in the archive extraction functionality of those versions.

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

Remediation

dbcve · scoped

Upgrade available Upgrade to 2.21.8.13 or later

Fixed in 2.21.8.13

Interim mitigation

Update WhatsApp for Android and WhatsApp Business for Android to version v2.21.8.13 or later to obtain the patched application with proper filename validation.

Recommended fix High confidence

WhatsApp for Android v2.21.8.13 or later | WhatsApp Business for Android v2.21.8.13 or later

Open the Google Play Store on your Android device
Search for "WhatsApp" or "WhatsApp Business" depending on which application is installed
Tap on the app and select "Update" to install the latest version
Alternatively, enable automatic app updates in the Play Store to ensure you receive security patches
After updating, verify the version by going to WhatsApp Settings > Help > About WhatsApp - ensure the version is 2.21.8.13 or later

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Whatsapp Scoped from the published advisory

Consultation2.0 h
Implementation4.0 h
Testing2.0 h
Review / QA1.0 h

9.0 hours of engineering $1,600

Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,560.

Scan for this in your stack

Free · runs locally

dbcve dependency scanner

Check whether your project pulls in CVE-2021-24035 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References

Primary sources

www.whatsapp.comVendor Advisory
nvd.nist.govNVD record

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-24035 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2021-24035?

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

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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

At a glance

A fix existsUpgrade to 2.21.8.13 or later

Severity 9.1 Critical

Exploit likelihood EPSS, next 30 days 1.1%

Affects: Whatsapp

Remediation

A high-priority fix

Fix this in Whatsapp 9 hrs · Low

Typical engagement from $1,600

Get a fix See the full breakdown ↓

A high-priority vulnerability. Send your environment and a specialist will scope CVE-2021-24035 and return a fixed quote and timeline.

You’ll deal with our team directly and deploy the reviewed fix to staging first — never straight to production.

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.

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.

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.

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.

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.

Check your environment

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.

Scan for this in your stack

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

Practitioner notes

No notes yet

Official description

Technical summary

Affected products & versions

CVSS breakdown

Am I affected?

Remediation

References