CVE-2026-21347: Adobe Bridge RCE Vulnerability

CVE-2026-21347 Overview

CVE-2026-21347 is an Integer Overflow or Wraparound vulnerability affecting Adobe Bridge versions 15.1.3, 16.0.1 and earlier. This vulnerability could result in arbitrary code execution in the context of the current user when a victim opens a specially crafted malicious file. The vulnerability is classified under CWE-190 (Integer Overflow or Wraparound).

Critical Impact

Successful exploitation allows attackers to execute arbitrary code with the privileges of the current user, potentially leading to complete system compromise, data theft, or installation of malware.

Affected Products

• Adobe Bridge versions 15.1.3 and earlier
• Adobe Bridge versions 16.0.1 and earlier
• Affected on both Apple macOS and Microsoft Windows platforms

Discovery Timeline

• 2026-02-10 - CVE-2026-21347 published to NVD
• 2026-02-11 - Last updated in NVD database

Technical Details for CVE-2026-21347

Vulnerability Analysis

This vulnerability stems from improper handling of integer arithmetic operations within Adobe Bridge's file parsing functionality. When processing certain file formats, the application performs calculations that can result in an integer overflow condition. This occurs when an arithmetic operation attempts to create a numeric value that exceeds the maximum value that can be stored in the allocated memory space, causing the value to "wrap around" to a much smaller number.

The integer overflow condition can lead to undersized buffer allocations, which subsequently results in heap-based memory corruption when the application writes more data than the buffer can hold. This memory corruption can be leveraged by attackers to achieve arbitrary code execution.

Root Cause

The root cause of CVE-2026-21347 is insufficient validation of integer values before they are used in memory allocation or buffer size calculations. When processing maliciously crafted files, Adobe Bridge fails to properly check for potential overflow conditions in arithmetic operations. This allows attackers to supply input that triggers integer wraparound, resulting in heap memory corruption that can be exploited for code execution.

Attack Vector

This vulnerability requires local access and user interaction to exploit. An attacker must craft a malicious file (such as an image or project file compatible with Adobe Bridge) and convince a user to open it. The attack vector involves:

1. Creating a specially crafted file containing values designed to trigger the integer overflow
2. Distributing the malicious file via email attachments, file-sharing platforms, or compromised websites
3. Waiting for a victim to open the file using a vulnerable version of Adobe Bridge
4. Upon file processing, the integer overflow triggers memory corruption
5. The attacker's payload executes with the current user's privileges

The vulnerability does not require elevated privileges to exploit, but successful exploitation grants the attacker the same access level as the victim user.

Detection Methods for CVE-2026-21347

Indicators of Compromise

• Unexpected crashes or instability in Adobe Bridge when opening files from untrusted sources
• Unusual child processes spawned by Adobe Bridge application
• Suspicious file access patterns following the opening of image or project files
• Memory corruption artifacts in system logs related to Adobe Bridge processes

Detection Strategies

• Monitor for unusual Adobe Bridge process behavior including unexpected child process creation
• Implement file integrity monitoring for Adobe Bridge installation directories
• Deploy endpoint detection rules that alert on Adobe Bridge spawning command shells or script interpreters
• Analyze incoming files through sandboxing solutions before allowing users to open them

Monitoring Recommendations

• Enable enhanced logging for Adobe Creative Cloud applications
• Monitor for suspicious network connections originating from Adobe Bridge processes
• Track file operations performed by Adobe Bridge, particularly when processing files from external sources
• Implement behavioral analysis to detect anomalous memory allocation patterns in Adobe Bridge

How to Mitigate CVE-2026-21347

Immediate Actions Required

• Update Adobe Bridge to the latest patched version immediately
• Restrict users from opening files received from untrusted or unknown sources until patching is complete
• Consider temporarily disabling or removing Adobe Bridge on critical systems if patching is not immediately possible
• Educate users about the risks of opening files from untrusted sources

Patch Information

Adobe has released security updates to address this vulnerability. Detailed patch information is available in Adobe Security Bulletin APSB26-21. Organizations should prioritize applying these updates, particularly on systems that frequently process files from external sources.

Workarounds

• Implement strict file source validation policies, only allowing files from trusted sources to be opened
• Use application sandboxing or virtualization to isolate Adobe Bridge from critical system resources
• Configure email gateways to quarantine or block file types commonly processed by Adobe Bridge from unknown senders
• Deploy SentinelOne endpoint protection to detect and prevent exploitation attempts targeting this vulnerability

# Verify Adobe Bridge version on macOS
mdls -name kMDItemVersion "/Applications/Adobe Bridge 2026/Adobe Bridge 2026.app"

# Check installed version on Windows (PowerShell)
Get-ItemProperty "HKLM:\SOFTWARE\Adobe\Adobe Bridge" | Select-Object -Property Version