CVE-2025-27158: Adobe Acrobat RCE Vulnerability

CVE-2025-27158 Overview

CVE-2025-27158 is an Access of Uninitialized Pointer vulnerability affecting Adobe Acrobat Reader. This memory corruption flaw exists in multiple versions of Adobe's PDF reader software and could allow attackers to achieve arbitrary code execution in the context of the current user. The vulnerability is classified as CWE-824 (Access of Uninitialized Pointer), indicating that the application accesses a pointer that has not been initialized, leading to unpredictable behavior and potential security compromise.

Exploitation of this vulnerability requires user interaction—specifically, a victim must open a maliciously crafted PDF file. Once triggered, an attacker could execute arbitrary code with the same privileges as the logged-in user, potentially leading to complete system compromise, data theft, or malware installation.

Critical Impact

Successful exploitation allows arbitrary code execution through malicious PDF files, potentially leading to full system compromise with user-level privileges.

Affected Products

• Adobe Acrobat versions prior to and including 24.001.30225 (Classic track)
• Adobe Acrobat Reader versions prior to and including 20.005.30748 (Classic track)
• Adobe Acrobat DC / Acrobat Reader DC versions prior to and including 25.001.20428 (Continuous track)
• Affected on both Microsoft Windows and Apple macOS platforms

Discovery Timeline

• March 11, 2025 - CVE-2025-27158 published to NVD
• April 28, 2025 - Last updated in NVD database

Technical Details for CVE-2025-27158

Vulnerability Analysis

The vulnerability stems from improper handling of pointer initialization within Adobe Acrobat's PDF parsing and rendering engine. When processing certain malformed PDF structures, the application attempts to access memory through a pointer that has not been properly initialized. This condition creates an exploitable memory corruption scenario where an attacker can control program execution flow.

Uninitialized pointer vulnerabilities are particularly dangerous because they can lead to use of arbitrary memory addresses. In this case, the vulnerability affects the PDF document processing pipeline, meaning any user who opens a specially crafted PDF file could trigger the condition. The attack requires local access (the user must open the file), but no special privileges are needed—standard user permissions are sufficient for exploitation.

Root Cause

The root cause of CVE-2025-27158 is the access of an uninitialized pointer (CWE-824) during PDF document processing. This occurs when Adobe Acrobat's code path reaches a point where it dereferences a pointer variable before proper initialization has occurred. The uninitialized memory may contain arbitrary data, which when treated as a valid pointer, can redirect program execution to attacker-controlled memory regions.

This type of vulnerability typically arises from:

• Missing initialization in certain code paths
• Error handling that bypasses initialization routines
• Complex object lifecycle management where pointers are accessed before construction completes

Attack Vector

The attack vector for CVE-2025-27158 is local, requiring user interaction. An attacker must craft a malicious PDF file containing specific structures designed to trigger the uninitialized pointer access. The attack chain typically follows this pattern:

1. Delivery: The attacker distributes the malicious PDF via email attachment, web download, or file sharing
2. User Interaction: The victim opens the PDF file using a vulnerable version of Adobe Acrobat or Acrobat Reader
3. Trigger: The malicious PDF structure causes the application to access an uninitialized pointer
4. Exploitation: The attacker leverages the memory corruption to redirect execution flow
5. Code Execution: Arbitrary code executes with the privileges of the current user

The vulnerability requires no authentication and can be exploited with low complexity once the user opens the malicious file. For detailed technical analysis, refer to the Talos Intelligence Vulnerability Report TALOS-2025-2135.

Detection Methods for CVE-2025-27158

Indicators of Compromise

• Abnormal crashes or unexpected behavior in Adobe Acrobat or Acrobat Reader processes
• Suspicious PDF files received via email or downloaded from untrusted sources
• Unexpected child processes spawned by AcroRd32.exe or Acrobat.exe
• Memory access violations or application error logs indicating pointer-related exceptions

Detection Strategies

• Deploy endpoint detection and response (EDR) solutions to monitor Adobe Acrobat process behavior for signs of exploitation
• Implement email gateway scanning to detect and quarantine malicious PDF attachments before delivery
• Configure application whitelisting to prevent unauthorized code execution from Acrobat processes
• Enable Windows Defender Exploit Guard or similar memory protection mechanisms

Monitoring Recommendations

• Monitor for unusual network connections initiated by Adobe Acrobat processes
• Review Windows Event Logs for application crashes with exception codes related to memory access violations (e.g., 0xC0000005)
• Implement file integrity monitoring on systems where Acrobat is installed to detect unauthorized modifications
• Enable enhanced logging for PDF file access patterns across the enterprise

How to Mitigate CVE-2025-27158

Immediate Actions Required

• Update Adobe Acrobat and Acrobat Reader to the latest patched versions immediately
• Implement user awareness training about the risks of opening PDF files from untrusted sources
• Enable Protected Mode and Enhanced Security in Adobe Acrobat Reader settings
• Consider deploying application sandboxing solutions for PDF viewing

Patch Information

Adobe has released security updates to address this vulnerability as documented in Adobe Security Advisory APSB25-14. Organizations should update to the following versions or later:

• Continuous Track: Acrobat DC and Acrobat Reader DC versions released after 25.001.20428
• Classic Track (2024): Acrobat and Acrobat Reader versions released after 24.001.30225
• Classic Track (2020): Acrobat and Acrobat Reader versions released after 20.005.30748

Administrators should prioritize patching for systems where users routinely handle PDF documents from external sources.

Workarounds

• Disable JavaScript in Adobe Acrobat Reader to reduce the attack surface (Edit → Preferences → JavaScript → uncheck "Enable Acrobat JavaScript")
• Use alternative PDF readers for viewing untrusted documents until patching is complete
• Configure email gateways to strip or quarantine PDF attachments from unknown senders
• Implement network segmentation to limit the impact of potential compromise

# Disable Adobe Acrobat JavaScript via Registry (Windows)
reg add "HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\DC\JSPrefs" /v bEnableJS /t REG_DWORD /d 0 /f

# Enable Protected Mode via Registry (Windows)  
reg add "HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\DC\Privileged" /v bProtectedMode /t REG_DWORD /d 1 /f