CVE-2024-49532: Adobe Acrobat Information Disclosure Flaw

CVE-2024-49532 Overview

CVE-2024-49532 is an out-of-bounds read vulnerability affecting Adobe Acrobat Reader that could lead to disclosure of sensitive memory. This memory corruption flaw allows an attacker to potentially bypass critical security mitigations such as Address Space Layout Randomization (ASLR). The vulnerability requires user interaction, as exploitation necessitates that a victim opens a specially crafted malicious PDF file.

Critical Impact

Successful exploitation could expose sensitive memory contents, enabling attackers to bypass ASLR protections and potentially chain with other vulnerabilities for more severe attacks.

Affected Products

• Adobe Acrobat versions 24.005.20307 and earlier (Continuous track)
• Adobe Acrobat Reader versions 24.001.30213, 24.001.30193 and earlier (Classic track)
• Adobe Acrobat DC versions 20.005.30730, 20.005.30710 and earlier
• Adobe Acrobat Reader DC (Continuous track)

Discovery Timeline

• 2024-12-10 - CVE-2024-49532 published to NVD
• 2025-02-06 - Last updated in NVD database

Technical Details for CVE-2024-49532

Vulnerability Analysis

This vulnerability stems from an out-of-bounds read condition (CWE-125) within Adobe Acrobat Reader's PDF parsing functionality. When processing certain malformed PDF structures, the application fails to properly validate buffer boundaries before performing read operations. This allows an attacker to craft a malicious PDF document that, when opened by a victim, triggers the application to read memory beyond the intended buffer boundaries.

The information disclosure resulting from this vulnerability is particularly concerning because it can expose memory addresses and layout information. This data can be leveraged to defeat ASLR, a critical exploit mitigation technology that randomizes memory addresses to prevent reliable exploitation of memory corruption vulnerabilities.

Root Cause

The root cause is an improper bounds checking mechanism during PDF document parsing. When processing specific PDF elements or structures, the application calculates memory offsets without adequately verifying that the resulting read operations remain within allocated buffer boundaries. This oversight allows read operations to access adjacent memory regions, potentially exposing sensitive data including memory layout information.

Attack Vector

The attack vector is local and requires user interaction. An attacker must craft a malicious PDF file containing specially constructed elements designed to trigger the out-of-bounds read condition. The attacker then needs to convince a victim to open this malicious file using a vulnerable version of Adobe Acrobat or Acrobat Reader.

The attack chain typically involves:

1. Crafting a malicious PDF with structures that exploit the boundary validation flaw
2. Distributing the malicious PDF via email, web download, or file sharing
3. Victim opening the PDF in a vulnerable Acrobat Reader version
4. Memory disclosure occurring during document processing
5. Attacker potentially using leaked information to bypass ASLR for subsequent exploitation

The vulnerability is documented in Talos Intelligence Vulnerability Report TALOS-2024-2064, which provides additional technical details on the exploitation mechanism.

Detection Methods for CVE-2024-49532

Indicators of Compromise

• Unusual PDF files with malformed or abnormally large data structures
• Adobe Acrobat or Reader processes exhibiting unexpected memory access patterns
• Crash dumps or error reports from Acrobat Reader indicating memory access violations
• PDF documents from untrusted sources being opened on endpoints

Detection Strategies

• Deploy endpoint detection rules to monitor Adobe Acrobat process behavior for signs of memory disclosure
• Implement file inspection at email gateways and web proxies to identify potentially malicious PDF structures
• Monitor for unexpected crashes or exceptions in AcroRd32.exe or Acrobat.exe processes
• Utilize SentinelOne's behavioral AI to detect exploitation attempts targeting PDF readers

Monitoring Recommendations

• Enable enhanced logging for Adobe Acrobat products on critical endpoints
• Configure security monitoring solutions to alert on suspicious PDF file activity
• Monitor network traffic for PDF downloads from untrusted or newly registered domains
• Track user-reported incidents involving unexpected Acrobat Reader behavior after opening PDF files

How to Mitigate CVE-2024-49532

Immediate Actions Required

• Update all Adobe Acrobat and Acrobat Reader installations to the latest patched versions immediately
• Restrict PDF file downloads and opening to verified trusted sources only
• Enable Protected View in Adobe Acrobat Reader settings for files from the internet
• Consider implementing application allowlisting to prevent unauthorized PDF readers from executing

Patch Information

Adobe has released security updates addressing this vulnerability in Adobe Security Bulletin APSB24-92. Organizations should prioritize updating to the following minimum versions:

• Acrobat DC (Continuous): Update to version newer than 24.005.20307
• Acrobat 2024 (Classic): Update to version newer than 24.001.30213
• Acrobat 2020 (Classic): Update to version newer than 20.005.30730
• Acrobat Reader DC: Apply the latest available security update

Workarounds

• Enable Protected View for all PDF files: Settings → Security (Enhanced) → Protected View → All files
• Disable JavaScript in Adobe Reader: Preferences → JavaScript → uncheck "Enable Acrobat JavaScript"
• Configure enterprise Group Policy to enforce Protected View across all managed endpoints
• Consider using alternative PDF viewers for documents from untrusted sources until patching is complete

# Configuration example: Enable Protected View via Windows Registry for enterprise deployment
# Apply to Acrobat Reader DC
reg add "HKCU\Software\Adobe\Acrobat Reader\DC\TrustManager" /v bProtectedMode /t REG_DWORD /d 1 /f
reg add "HKCU\Software\Adobe\Acrobat Reader\DC\TrustManager" /v bEnableProtectedViewForAllFiles /t REG_DWORD /d 1 /f

# Disable JavaScript in Acrobat Reader
reg add "HKCU\Software\Adobe\Acrobat Reader\DC\JSPrefs" /v bEnableJS /t REG_DWORD /d 0 /f