CVE-2025-54221: Adobe InCopy RCE Vulnerability

CVE-2025-54221 Overview

CVE-2025-54221 is an out-of-bounds write vulnerability [CWE-787] affecting Adobe InCopy versions 20.4, 19.5.4, and earlier. The flaw allows arbitrary code execution in the context of the current user when a victim opens a malicious file. Adobe published the issue on August 12, 2025, alongside security bulletin APSB25-80. The vulnerability requires local access and user interaction, limiting remote exploitation but exposing users targeted through phishing or supply chain delivery of crafted documents.

Critical Impact
Successful exploitation enables arbitrary code execution under the privileges of the user running InCopy, which can lead to full workstation compromise on Windows and macOS systems.

Affected Products

Adobe InCopy 20.4 and earlier 20.x releases
Adobe InCopy 19.5.4 and earlier 19.x releases
Microsoft Windows and Apple macOS installations running affected InCopy versions

Discovery Timeline

2025-08-12 - CVE-2025-54221 published to NVD and Adobe releases security bulletin APSB25-80
2025-08-13 - Last updated in NVD database

Technical Details for CVE-2025-54221

Vulnerability Analysis

The vulnerability is an out-of-bounds write condition in Adobe InCopy's file parsing logic. InCopy is a professional word processor that integrates with Adobe InDesign for collaborative editorial workflows. When the application processes a malformed document, it writes data past the bounds of an allocated buffer.

An attacker who controls the out-of-bounds write can corrupt adjacent memory structures. Skilled exploitation typically pivots from memory corruption into control of execution flow, resulting in arbitrary code execution within the InCopy process. The resulting code runs with the privileges of the user opening the file.

Exploitation requires user interaction. The victim must open a malicious .icml, .indd, or related document. This pattern is consistent with prior Adobe Creative Cloud document parser vulnerabilities and is commonly delivered through targeted phishing or compromised collaboration channels.

Root Cause

The root cause is missing or insufficient bounds validation when parsing attacker-controlled fields inside an InCopy document. The parser trusts length or offset values supplied by the file, allowing write operations to exceed the allocated buffer. This maps directly to CWE-787: Out-of-bounds Write.

Attack Vector

The attack vector is local with user interaction. An attacker crafts a malicious InCopy document and delivers it through email attachments, shared editorial workflows, cloud storage links, or removable media. When the victim opens the file in a vulnerable InCopy installation, the parser triggers the out-of-bounds write and the attacker's payload executes.

The vulnerability manifests in InCopy's document parsing routines. Adobe has not published low-level technical details, and no public proof-of-concept code is available. See Adobe Security Advisory APSB25-80 for vendor guidance.

Detection Methods for CVE-2025-54221

Indicators of Compromise

Unexpected child processes spawned by InCopy.exe on Windows or the InCopy process on macOS, particularly shells, scripting hosts, or LOLBins such as powershell.exe, cmd.exe, or osascript
InCopy process crashes or anomalous memory access violations recorded in Windows Event Logs or macOS crash reports shortly after opening a document
Inbound InCopy documents (.icml, .indd, .idml) arriving from untrusted senders or unusual external sources
New persistence artifacts, scheduled tasks, or LaunchAgents created in the same session that InCopy opened a document

Detection Strategies

Hunt for process lineage where InCopy is the parent of interactive shells, scripting engines, or network utilities
Monitor for outbound network connections initiated by the InCopy process to non-Adobe infrastructure
Apply YARA or static signatures to email gateways and file shares that flag malformed InCopy document structures
Correlate document open events with subsequent file system writes to user-writable autorun locations

Monitoring Recommendations

Enable command-line and process creation logging on Windows endpoints and execve auditing on macOS to capture child processes of InCopy
Ingest endpoint telemetry, mail gateway logs, and Adobe application crash data into a centralized analytics platform for correlation
Track InCopy version inventory across the fleet to identify endpoints still running 20.4, 19.5.4, or earlier

How to Mitigate CVE-2025-54221

Immediate Actions Required

Apply the updates listed in Adobe Security Bulletin APSB25-80 to all Windows and macOS systems running InCopy
Identify and prioritize endpoints used by editorial, marketing, and design teams that routinely open external documents
Restrict opening of InCopy documents received from untrusted or external sources until patching is verified
Enforce least-privilege accounts for users running Creative Cloud applications to limit the impact of code execution

Patch Information

Adobe released fixed versions of InCopy in security bulletin APSB25-80 on August 12, 2025. Administrators should upgrade to the patched releases identified in the Adobe Security Advisory APSB25-80. Updates are distributed through the Adobe Creative Cloud desktop application and Adobe's enterprise deployment tooling.

Workarounds

Block delivery of InCopy document formats at email gateways from external senders where business workflows allow
Open suspicious documents only inside isolated virtual machines or sandboxed environments without network access
Use application allowlisting to prevent InCopy from spawning shells, scripting interpreters, or unsigned binaries
Disable automatic preview or rendering of InCopy documents in collaboration platforms and file managers

bash

# Verify installed InCopy version on macOS
/usr/bin/mdls -name kMDItemVersion "/Applications/Adobe InCopy 2024/Adobe InCopy 2024.app"

# Query installed InCopy version on Windows via PowerShell
Get-ItemProperty "HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\*" |
  Where-Object { $_.DisplayName -like "*InCopy*" } |
  Select-Object DisplayName, DisplayVersion