CVE-2021-30045 – CVE-2021-30045 is a buffer overflow vulnerabili... (How to Fix)

Q: What is the severity of CVE-2021-30045?

CVE-2021-30045 has a CVSS score of 9.1 (CRITICAL). CVE-2021-30045 is a buffer overflow vulnerability in SerenityOS's EndOfCentralDirectory::read() function that allows attackers to execute arbitrary code or cause denial of service. This affects users running SerenityOS 2021-03-27 or earlier versions. The vulnerability stems from improper bounds checking when processing ZIP archive structures.

📋 TL;DR

CVE-2021-30045 is a buffer overflow vulnerability in SerenityOS's EndOfCentralDirectory::read() function that allows attackers to execute arbitrary code or cause denial of service. This affects users running SerenityOS 2021-03-27 or earlier versions. The vulnerability stems from improper bounds checking when processing ZIP archive structures.

💻 Affected Systems

Products:

SerenityOS

Versions: Versions up to and including 2021-03-27

Operating Systems: SerenityOS

Default Config Vulnerable: ⚠️ Yes

Notes: All default installations of affected SerenityOS versions are vulnerable when processing ZIP archives.

📦 What is this software?

Serenityos by Serenityos

View all CVEs affecting Serenityos →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote code execution leading to complete system compromise, data theft, or persistent backdoor installation.

🟠

Likely Case

Application crash (denial of service) or limited code execution within the context of the affected process.

🟢

If Mitigated

No impact if patched or if vulnerable functionality is disabled through security controls.

🌐 Internet-Facing: MEDIUM - Requires processing malicious ZIP files, which could occur through web uploads or downloads.

🏢 Internal Only: LOW - Primarily affects local file processing unless malicious ZIP files are introduced internally.

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: LIKELY

Unauthenticated Exploit: ⚠️ Yes

Complexity: LOW

Exploitation requires the victim to process a specially crafted ZIP file. The vulnerability is well-documented in public repositories.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Fixed in commit 4317db7498eaa5a37068052bb0310fbc6a5f78e4 and later

Vendor Advisory: https://github.com/SerenityOS/serenity/commit/4317db7498eaa5a37068052bb0310fbc6a5f78e4

Restart Required: Yes

Instructions:

1. Update SerenityOS to a version after commit 4317db7498eaa5a37068052bb0310fbc6a5f78e4. 2. Rebuild and redeploy the system. 3. Restart affected services or the entire system.

🔧 Temporary Workarounds

Disable ZIP processing

all

Temporarily disable or restrict processing of ZIP archives in SerenityOS applications.

# Configuration depends on specific application usage

🧯 If You Can't Patch

Implement strict input validation for ZIP files before processing
Use application sandboxing or containerization to limit potential damage

🔍 How to Verify

Check if Vulnerable:

Check SerenityOS version: if it's 2021-03-27 or earlier, it's vulnerable.

Check Version:

Check SerenityOS build date or version information in system settings

Verify Fix Applied:

Verify the system includes commit 4317db7498eaa5a37068052bb0310fbc6a5f78e4 or later in its git history.

📡 Detection & Monitoring

Log Indicators:

Application crashes when processing ZIP files
Memory access violation errors in system logs

Network Indicators:

Unusual network connections following ZIP file processing

SIEM Query:

Search for process crashes related to ZIP handling or memory corruption events

📊 Metadata

CVE ID: CVE-2021-30045

CVSS v3 Score: 9.1 (CRITICAL)

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

CWE: CWE-120

Published: April 6, 2021

Last Updated: November 21, 2024

🔗 References

https://github.com/SerenityOS/serenity/commit/4317db7498eaa5a37068052bb0310fbc6a5f78e4 Patch,Third Party Advisory
https://github.com/SerenityOS/serenity/issues/5975 Third Party Advisory
https://github.com/SerenityOS/serenity/pull/5977 Third Party Advisory
https://github.com/SerenityOS/serenity/commit/4317db7498eaa5a37068052bb0310fbc6a5f78e4 Patch,Third Party Advisory
https://github.com/SerenityOS/serenity/issues/5975 Third Party Advisory
https://github.com/SerenityOS/serenity/pull/5977 Third Party Advisory

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🔗 Related Vulnerabilities

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