CVE-2021-45055
📋 TL;DR
Adobe InCopy versions 16.4 and earlier contain an out-of-bounds read vulnerability when parsing malicious files. An attacker can exploit this to execute arbitrary code with the privileges of the current user. Exploitation requires user interaction through opening a crafted file.
💻 Affected Systems
- Adobe InCopy
📦 What is this software?
Incopy by Adobe
⚠️ Risk & Real-World Impact
Worst Case
Full system compromise via arbitrary code execution with user privileges, potentially leading to data theft, ransomware deployment, or lateral movement.
Likely Case
Limited code execution within the application context, potentially causing application crashes or limited data exposure.
If Mitigated
No impact if users don't open untrusted files or if application is patched.
🎯 Exploit Status
Exploitation requires user interaction (opening malicious file) and bypassing memory protections.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 16.4.1 or later
Vendor Advisory: https://helpx.adobe.com/security/products/incopy/apsb22-04.html
Restart Required: Yes
Instructions:
1. Open Adobe InCopy. 2. Go to Help > Check for Updates. 3. Follow prompts to install version 16.4.1 or later. 4. Restart the application.
🔧 Temporary Workarounds
Restrict file opening
allConfigure application to only open trusted files or disable automatic file opening.
Application sandboxing
allRun Adobe InCopy in a sandboxed environment to limit potential damage.
🧯 If You Can't Patch
- Implement application whitelisting to prevent execution of vulnerable versions
- Educate users about risks of opening untrusted files and implement email filtering for malicious attachments
🔍 How to Verify
Check if Vulnerable:
Check Adobe InCopy version via Help > About InCopy. If version is 16.4 or earlier, system is vulnerable.Check Version:
On Windows: wmic product where name="Adobe InCopy" get version. On macOS: /Applications/Adobe\ InCopy\ 2022/Adobe\ InCopy\ 2022.app/Contents/MacOS/Adobe\ InCopy\ 2022 --versionVerify Fix Applied:
Verify version is 16.4.1 or later in Help > About InCopy.📡 Detection & Monitoring
Log Indicators:
- Application crashes with memory access violations
- Unexpected file parsing errors
Network Indicators:
- Downloads of suspicious InCopy files from untrusted sources
SIEM Query:
EventID=1000 OR EventID=1001 AND ProcessName="Adobe InCopy.exe" AND ExceptionCode=0xC0000005