CVE-2021-32263 – CVE-2021-32263 is a heap-based buffer overflow ... (How to Fix)

Q: What is the severity of CVE-2021-32263?

CVE-2021-32263 has a CVSS score of 7.8 (HIGH). CVE-2021-32263 is a heap-based buffer overflow vulnerability in ok-file-formats library's CSV parsing functionality. Attackers can exploit this by providing malicious CSV files to cause arbitrary code execution or application crashes. Any application using vulnerable versions of ok-file-formats to parse CSV files is affected.

📋 TL;DR

CVE-2021-32263 is a heap-based buffer overflow vulnerability in ok-file-formats library's CSV parsing functionality. Attackers can exploit this by providing malicious CSV files to cause arbitrary code execution or application crashes. Any application using vulnerable versions of ok-file-formats to parse CSV files is affected.

💻 Affected Systems

Products:

ok-file-formats library
Applications embedding ok-file-formats

Versions: All versions through 2021-04-29

Operating Systems: All platforms where ok-file-formats is used

Default Config Vulnerable: ⚠️ Yes

Notes: Vulnerability triggers when parsing CSV files via ok_csv_circular_buffer_read function.

📦 What is this software?

Ok File Formats by Ok File Formats Project

View all CVEs affecting Ok File Formats →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote code execution leading to complete system compromise, data theft, or ransomware deployment.

🟠

Likely Case

Application crash (denial of service) or limited memory corruption allowing information disclosure.

🟢

If Mitigated

Application crash with no further impact if proper sandboxing and memory protections are enabled.

🌐 Internet-Facing: MEDIUM - Requires user to upload or process malicious CSV files, but common in web applications.

🏢 Internal Only: MEDIUM - Internal users could exploit via file upload features or shared documents.

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: LIKELY

Unauthenticated Exploit: ⚠️ Yes

Complexity: LOW

Proof of concept available in GitHub issue. Exploitation requires user to process malicious CSV file.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Versions after 2021-04-29

Vendor Advisory: https://github.com/brackeen/ok-file-formats/issues/13

Restart Required: Yes

Instructions:

1. Update ok-file-formats to version after 2021-04-29. 2. Rebuild applications using the library. 3. Restart affected services.

🔧 Temporary Workarounds

Disable CSV Processing

all

Temporarily disable CSV file parsing functionality in applications.

Input Validation

all

Implement strict CSV file validation before processing.

🧯 If You Can't Patch

Implement application sandboxing to limit impact of potential exploitation
Use memory protection features like ASLR and DEP

🔍 How to Verify

Check if Vulnerable:

Check if application uses ok-file-formats version 2021-04-29 or earlier.

Check Version:

Check library version in source code or build configuration files.

Verify Fix Applied:

Verify ok-file-formats version is after 2021-04-29 and applications have been rebuilt.

📡 Detection & Monitoring

Log Indicators:

Application crashes during CSV processing
Memory access violation errors

Network Indicators:

Unusual CSV file uploads to web applications

SIEM Query:

source="application.log" AND ("segmentation fault" OR "access violation") AND "csv"

📊 Metadata

CVE ID: CVE-2021-32263

CVSS v3 Score: 7.8 (HIGH)

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

CWE: CWE-787

Published: August 24, 2021

Last Updated: November 21, 2024

🔗 References

https://github.com/brackeen/ok-file-formats/issues/13 Exploit,Patch,Third Party Advisory
https://github.com/brackeen/ok-file-formats/issues/13 Exploit,Patch,Third Party Advisory

📤 Share & Export

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🔗 Related Vulnerabilities

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