CVE-2020-1891 – This vulnerability in WhatsApp allows attackers... (How to Fix)

Q: What is the severity of CVE-2020-1891?

CVE-2020-1891 has a CVSS score of 9.8 (CRITICAL). This vulnerability in WhatsApp allows attackers to trigger an out-of-bounds write via a user-controlled parameter during video calls. Successful exploitation could lead to remote code execution or application crashes. Affected users include those running vulnerable versions of WhatsApp on 32-bit Android and iOS devices.

📋 TL;DR

This vulnerability in WhatsApp allows attackers to trigger an out-of-bounds write via a user-controlled parameter during video calls. Successful exploitation could lead to remote code execution or application crashes. Affected users include those running vulnerable versions of WhatsApp on 32-bit Android and iOS devices.

💻 Affected Systems

Products:

WhatsApp for Android
WhatsApp Business for Android
WhatsApp for iPhone
WhatsApp Business for iPhone

Versions: Android prior to v2.20.17, WhatsApp Business for Android prior to v2.20.7, iPhone prior to v2.20.20, WhatsApp Business for iPhone prior to v2.20.20

Operating Systems: Android, iOS

Default Config Vulnerable: ⚠️ Yes

Notes: Only affects 32-bit devices. 64-bit devices are not vulnerable.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote code execution allowing complete compromise of the WhatsApp application and potentially the underlying device.

🟠

Likely Case

Application crash leading to denial of service and potential data corruption.

🟢

If Mitigated

No impact if patched versions are installed.

🌐 Internet-Facing: HIGH - Attack can be triggered remotely via video calls.

🏢 Internal Only: LOW - The vulnerability requires external interaction via WhatsApp's video call feature.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ⚠️ Yes

Complexity: MEDIUM

Exploitation requires initiating a video call with malicious parameters. No public exploit code is known.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Android v2.20.17+, WhatsApp Business for Android v2.20.7+, iPhone v2.20.20+, WhatsApp Business for iPhone v2.20.20+

Vendor Advisory: https://www.whatsapp.com/security/advisories/2020

Restart Required: No

Instructions:

1. Open WhatsApp app store (Google Play Store or Apple App Store). 2. Check for updates. 3. Install the latest version. 4. The app will automatically apply the patch without requiring a restart.

🔧 Temporary Workarounds

Disable video calls

all

Temporarily disable video call functionality to prevent exploitation.

Not applicable - manual app setting change

🧯 If You Can't Patch

Use alternative messaging applications for video calls
Restrict WhatsApp usage to trusted contacts only

🔍 How to Verify

Check if Vulnerable:

Check WhatsApp version in app settings: Settings > Help > App Info. Compare against vulnerable versions.

Check Version:

Not applicable - check via app settings menu

Verify Fix Applied:

Confirm version is equal to or higher than patched versions: Android v2.20.17+, WhatsApp Business for Android v2.20.7+, iPhone v2.20.20+, WhatsApp Business for iPhone v2.20.20+

📡 Detection & Monitoring

Log Indicators:

Unexpected WhatsApp crashes during video calls
Memory access violation logs on device

Network Indicators:

Unusual video call patterns from unknown contacts
Video calls with abnormal parameter sizes

SIEM Query:

Not applicable for mobile device monitoring

📊 Metadata

CVE ID: CVE-2020-1891

CVSS v3 Score: 9.8 (CRITICAL)

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

CWE: CWE-787

Published: September 3, 2020

Last Updated: November 21, 2024

🔗 References

https://www.whatsapp.com/security/advisories/2020 Vendor Advisory
https://www.whatsapp.com/security/advisories/2020 Vendor Advisory

📤 Share & Export

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🔗 Related Vulnerabilities

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