CVE-2020-4448 – CVE-2020-4448 is a critical deserialization vul... (How to Fix)

Q: What is the severity of CVE-2020-4448?

CVE-2020-4448 has a CVSS score of 9.8 (CRITICAL). CVE-2020-4448 is a critical deserialization vulnerability in IBM WebSphere Application Server that allows remote attackers to execute arbitrary code by sending specially crafted serialized objects. This affects WebSphere Network Deployment versions 7.0, 8.0, 8.5, and 9.0. Attackers can achieve remote code execution without authentication.

📋 TL;DR

CVE-2020-4448 is a critical deserialization vulnerability in IBM WebSphere Application Server that allows remote attackers to execute arbitrary code by sending specially crafted serialized objects. This affects WebSphere Network Deployment versions 7.0, 8.0, 8.5, and 9.0. Attackers can achieve remote code execution without authentication.

💻 Affected Systems

Products:

IBM WebSphere Application Server Network Deployment

Versions: 7.0, 8.0, 8.5, 9.0

Operating Systems: All supported platforms (Windows, Linux, AIX, Solaris, etc.)

Default Config Vulnerable: ⚠️ Yes

Notes: Affects all configurations where WebSphere is deployed. The vulnerability is in the core application server components.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

Complete system compromise with attacker gaining full control over the server, potentially leading to data theft, ransomware deployment, or lateral movement within the network.

🟠

Likely Case

Remote code execution leading to web application compromise, data exfiltration, and installation of backdoors or malware.

🟢

If Mitigated

Limited impact if proper network segmentation, strict firewall rules, and updated systems prevent exploitation attempts.

🌐 Internet-Facing: HIGH

🏢 Internal Only: HIGH

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: CONFIRMED

Unauthenticated Exploit: ⚠️ Yes

Complexity: LOW

Exploit code is publicly available and has been weaponized in attacks. The vulnerability requires no authentication and has low attack complexity.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Apply Interim Fixes or Fix Packs as specified in IBM advisory

Vendor Advisory: https://www.ibm.com/support/pages/node/6220336

Restart Required: Yes

Instructions:

1. Review IBM advisory for specific fix versions. 2. Download appropriate fix from IBM Fix Central. 3. Apply fix following IBM installation procedures. 4. Restart WebSphere Application Server.

🔧 Temporary Workarounds

Restrict Network Access

all

Limit access to WebSphere administrative ports to trusted IP addresses only

Configure firewall rules to restrict access to ports 9060, 9043, 9080, 9443, and other WebSphere ports

Disable Unnecessary Services

all

Disable SOAP connector if not required

In WebSphere admin console: Servers > Server Types > WebSphere application servers > server_name > Ports > SOAP_CONNECTOR_ADDRESS > uncheck 'Enabled'

🧯 If You Can't Patch

Implement strict network segmentation and firewall rules to limit access to WebSphere servers
Deploy web application firewall (WAF) with rules to detect and block deserialization attacks

🔍 How to Verify

Check if Vulnerable:

Check WebSphere version via admin console or command: /opt/IBM/WebSphere/AppServer/bin/versionInfo.sh (Linux) or %WAS_HOME%\bin\versionInfo.bat (Windows)

Check Version:

/opt/IBM/WebSphere/AppServer/bin/versionInfo.sh

Verify Fix Applied:

Verify applied fix by checking versionInfo output shows patched version or check fix installation logs

📡 Detection & Monitoring

Log Indicators:

Unusual deserialization errors in SystemOut.log
Unexpected Java class loading
Suspicious network connections from WebSphere process

Network Indicators:

Unusual traffic to WebSphere administrative ports (9060, 9043)
Malformed serialized objects in network traffic

SIEM Query:

source="websphere" AND ("deserialization" OR "ClassNotFoundException" OR "InvalidClassException")

📊 Metadata

CVE ID: CVE-2020-4448

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-502

Published: June 5, 2020

Last Updated: November 21, 2024

🔗 References

https://exchange.xforce.ibmcloud.com/vulnerabilities/181228 VDB Entry,Vendor Advisory
https://www.ibm.com/support/pages/node/6220336 Patch,Vendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-20-688/ Third Party Advisory,VDB Entry
https://exchange.xforce.ibmcloud.com/vulnerabilities/181228 VDB Entry,Vendor Advisory
https://www.ibm.com/support/pages/node/6220336 Patch,Vendor Advisory
https://www.zerodayinitiative.com/advisories/ZDI-20-688/ Third Party Advisory,VDB Entry

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