CVE-2025-21157: Adobe InDesign RCE Vulnerability

CVE-2025-21157 Overview

CVE-2025-21157 is an out-of-bounds write vulnerability [CWE-787] affecting Adobe InDesign Desktop versions ID20.0, ID19.5.1, and earlier. Successful exploitation allows an attacker to execute arbitrary code in the context of the current user. The flaw requires user interaction, as a victim must open a maliciously crafted InDesign file for the exploit to trigger. Adobe addressed the issue in security bulletin APSB25-01. The vulnerability affects both Windows and macOS installations of InDesign.

Critical Impact
Attackers can achieve arbitrary code execution on a victim system by delivering a malicious InDesign document, gaining the privileges of the current user.

Affected Products

Adobe InDesign Desktop ID20.0
Adobe InDesign Desktop ID19.5.1 and earlier
Windows and macOS platforms

Discovery Timeline

2025-02-11 - CVE-2025-21157 published to the National Vulnerability Database
2025-03-03 - Last updated in NVD database

Technical Details for CVE-2025-21157

Vulnerability Analysis

The vulnerability is an out-of-bounds write condition within Adobe InDesign's file parsing logic. When InDesign processes a crafted document, it writes data past the bounds of an allocated buffer. This memory corruption can be leveraged to overwrite adjacent data structures, function pointers, or control-flow metadata. An attacker who controls the contents of the malicious file can steer execution toward attacker-supplied code. Because InDesign runs in user mode, the resulting code executes with the privileges of the user opening the file.

Root Cause

The root cause is improper validation of bounds during a write operation in InDesign's document parsing routines, classified under [CWE-787]. Insufficient size checks on file-derived data allow the application to write beyond the boundaries of a destination buffer. Adobe has not publicly disclosed the specific function or component involved.

Attack Vector

Exploitation requires local user interaction. The attack vector is AV:L with UI:R, meaning the attacker must deliver a crafted .indd or related InDesign file and convince a user to open it. Typical delivery methods include email attachments, file-sharing platforms, or compromised design asset repositories. No elevated privileges are required to trigger the flaw.

No public proof-of-concept exploit is available for CVE-2025-21157, and the issue is not listed in the CISA Known Exploited Vulnerabilities catalog. See the Adobe InDesign Security Advisory for vendor technical details.

Detection Methods for CVE-2025-21157

Indicators of Compromise

Unexpected InDesign process crashes or abnormal termination when opening third-party documents
Child processes spawned by InDesign.exe (Windows) or Adobe InDesign 2024/2025 (macOS) such as command shells or scripting interpreters
InDesign processes making outbound network connections shortly after opening a document
Creation or modification of executables or persistence artifacts following InDesign file opens

Detection Strategies

Monitor for anomalous child process creation from InDesign binaries, which is uncommon in normal design workflows
Inspect inbound .indd, .indt, and .idml files at email and web gateways for malformed structures
Correlate document-open events with subsequent process, file, and network activity to identify exploitation chains

Monitoring Recommendations

Enable endpoint telemetry for process lineage, file writes, and outbound connections originating from InDesign
Track InDesign versions across the fleet to identify hosts still running ID20.0, ID19.5.1, or earlier
Alert on InDesign process crashes with exception codes consistent with memory corruption such as 0xC0000005

How to Mitigate CVE-2025-21157

Immediate Actions Required

Update Adobe InDesign to the fixed version listed in Adobe security bulletin APSB25-01 on all Windows and macOS endpoints
Inventory all InDesign installations and prioritize patching hosts handling externally sourced documents
Instruct users not to open InDesign files from untrusted senders or unverified sources until patching is complete

Patch Information

Adobe released fixed versions of InDesign Desktop in security bulletin APSB25-01. Refer to the Adobe InDesign Security Advisory for exact target versions and download locations for Windows and macOS.

Workarounds

Restrict opening of InDesign documents originating outside the organization until patches are applied
Use application allowlisting and gateway filtering to block delivery of unsolicited .indd, .indt, and .idml files
Run InDesign under standard user accounts to limit the impact of successful code execution

bash

# Verify installed Adobe InDesign version on macOS
defaults read "/Applications/Adobe InDesign 2024/Adobe InDesign 2024.app/Contents/Info.plist" CFBundleShortVersionString

# Verify installed Adobe InDesign version on Windows (PowerShell)
Get-ItemProperty "HKLM:\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\*" |
  Where-Object { $_.DisplayName -like "*InDesign*" } |
  Select-Object DisplayName, DisplayVersion