CVE-2018-12932 – CVE-2018-12932 is a heap-based buffer overflow ... (How to Fix)

Q: What is the severity of CVE-2018-12932?

CVE-2018-12932 has a CVSS score of 9.8 (CRITICAL). CVE-2018-12932 is a heap-based buffer overflow vulnerability in Wine's PlayEnhMetaFileRecord function that allows attackers to cause denial of service or potentially execute arbitrary code. The vulnerability affects Wine 3.7 and earlier versions when processing Enhanced Metafile (EMF) records with manipulated pAlphaBlend->cbBitsSrc values. Users running Wine on Linux/Unix systems to run Windows applications are affected.

📋 TL;DR

CVE-2018-12932 is a heap-based buffer overflow vulnerability in Wine's PlayEnhMetaFileRecord function that allows attackers to cause denial of service or potentially execute arbitrary code. The vulnerability affects Wine 3.7 and earlier versions when processing Enhanced Metafile (EMF) records with manipulated pAlphaBlend->cbBitsSrc values. Users running Wine on Linux/Unix systems to run Windows applications are affected.

💻 Affected Systems

Products:

Wine

Versions: Wine 3.7 and earlier versions

Operating Systems: Linux, Unix-like systems, macOS

Default Config Vulnerable: ⚠️ Yes

Notes: Only affects systems running Wine to execute Windows applications. The vulnerability is in the EMF processing component.

📦 What is this software?

Wine by Winehq

View all CVEs affecting Wine →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote code execution leading to complete system compromise if an attacker can trigger the vulnerability through malicious EMF content.

🟠

Likely Case

Denial of service (application crash) when processing specially crafted EMF files or content.

🟢

If Mitigated

Application crash without privilege escalation if proper sandboxing and memory protections are in place.

🌐 Internet-Facing: MEDIUM - Requires user interaction (opening malicious content) but could be triggered through web content or email attachments.

🏢 Internal Only: LOW - Requires local access or user interaction with malicious files.

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: LIKELY

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Proof of concept exists in bug reports. Exploitation requires user interaction to process malicious EMF content. No known widespread weaponization.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Wine 3.8 and later

Vendor Advisory: https://bugs.winehq.org/show_bug.cgi?id=45105

Restart Required: Yes

Instructions:

1. Update Wine to version 3.8 or later using your package manager. 2. For Ubuntu/Debian: sudo apt update && sudo apt upgrade wine. 3. For source builds: git pull from wine repository and rebuild.

🔧 Temporary Workarounds

Disable EMF processing

linux

Prevent Wine from processing Enhanced Metafile records by modifying configuration or using application sandboxing.

Not applicable - requires application-level configuration changes

🧯 If You Can't Patch

Isolate Wine applications in containers or VMs to limit potential impact
Implement strict file handling policies to prevent processing untrusted EMF files

🔍 How to Verify

Check if Vulnerable:

Check Wine version: wine --version. If version is 3.7 or earlier, system is vulnerable.

Check Version:

wine --version

Verify Fix Applied:

Verify Wine version is 3.8 or later: wine --version. Test with known proof-of-concept EMF files.

📡 Detection & Monitoring

Log Indicators:

Wine application crashes with segmentation faults
Memory access violation errors in system logs

Network Indicators:

Unusual network connections from Wine processes post-crash

SIEM Query:

process.name:"wine" AND (event.type:"segmentation_fault" OR event.type:"memory_violation")

📊 Metadata

CVE ID: CVE-2018-12932

CVSS v3 Score: 9.8 (CRITICAL)

CVSS Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE: CWE-787

Published: June 28, 2018

Last Updated: November 21, 2024

🔗 References

https://bugs.launchpad.net/ubuntu/+source/wine/+bug/1764719 Issue Tracking,Third Party Advisory
https://bugs.winehq.org/attachment.cgi?id=61284 Issue Tracking,Patch,Third Party Advisory
https://bugs.winehq.org/show_bug.cgi?id=45105 Issue Tracking,Patch,Third Party Advisory
https://source.winehq.org/git/wine.git/commit/8d2676fd14f130f9e8f06744743423168bf8d18d Issue Tracking,Patch,Third Party Advisory
https://source.winehq.org/git/wine.git/commit/b6da3547d8990c3c3affc3a5865aefd2a0946949 Issue Tracking,Patch,Third Party Advisory
https://bugs.launchpad.net/ubuntu/+source/wine/+bug/1764719 Issue Tracking,Third Party Advisory
https://bugs.winehq.org/attachment.cgi?id=61284 Issue Tracking,Patch,Third Party Advisory
https://bugs.winehq.org/show_bug.cgi?id=45105 Issue Tracking,Patch,Third Party Advisory
https://source.winehq.org/git/wine.git/commit/8d2676fd14f130f9e8f06744743423168bf8d18d Issue Tracking,Patch,Third Party Advisory
https://source.winehq.org/git/wine.git/commit/b6da3547d8990c3c3affc3a5865aefd2a0946949 Issue Tracking,Patch,Third Party Advisory

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2018-12932, you might also want to check these: