CVE-2024-20727: Adobe Acrobat DC RCE Vulnerability

CVE-2024-20727 Overview

CVE-2024-20727 is an out-of-bounds write vulnerability [CWE-787] affecting Adobe Acrobat and Adobe Acrobat Reader. Versions 20.005.30539, 23.008.20470, and earlier releases on both Windows and macOS contain the flaw. Successful exploitation allows arbitrary code execution in the context of the current user. The attack requires user interaction, as a victim must open a crafted malicious file for the vulnerability to trigger. Adobe published fixes in the APSB24-07 security bulletin.

Critical Impact
Attackers who convince a user to open a malicious PDF can execute arbitrary code with the privileges of the current user, enabling malware installation, credential theft, or lateral movement.

Affected Products

Adobe Acrobat DC and Adobe Acrobat Reader DC (Continuous track) through 23.008.20470
Adobe Acrobat and Adobe Acrobat Reader (Classic track) through 20.005.30539
Windows and macOS installations of the above products

Discovery Timeline

2024-02-15 - CVE-2024-20727 published to NVD following Adobe security bulletin APSB24-07
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-20727

Vulnerability Analysis

The flaw is an out-of-bounds write [CWE-787] within Adobe Acrobat and Acrobat Reader's document processing code. When the application parses a specially crafted PDF, it writes data past the boundaries of an allocated buffer. Attackers can shape the out-of-bounds write to corrupt adjacent memory structures, hijack control flow, and execute arbitrary code. The resulting code runs in the security context of the user who opened the document, inheriting that user's file system and network privileges.

Adobe's advisory rates the impact against confidentiality, integrity, and availability as high, consistent with arbitrary code execution outcomes. The vulnerability requires a local attack vector because the target must open the malicious file on the affected system. The EPSS probability for exploitation is approximately 2%, placing it in the 79th percentile of tracked vulnerabilities.

Root Cause

The root cause is missing or insufficient bounds checking during the parsing of attacker-controlled fields inside a PDF document. When the parser calculates a write offset or length based on values embedded in the file, it fails to constrain those values to the destination buffer's allocated size. Adobe has not published detailed technical internals for CVE-2024-20727 beyond the advisory.

Attack Vector

Exploitation begins with delivery of a malicious PDF through email attachments, web downloads, messaging platforms, or shared file storage. The victim must open the document in a vulnerable Acrobat or Reader build. Once parsed, the crafted objects trigger the out-of-bounds write, and a chained exploit primitive achieves arbitrary code execution. Attackers commonly pair such flaws with sandbox escapes or living-off-the-land binaries to persist on the host.

No public proof-of-concept exploit is referenced in the enriched data. CISA has not added CVE-2024-20727 to the Known Exploited Vulnerabilities catalog.

Detection Methods for CVE-2024-20727

Indicators of Compromise

Acrobat or Reader (Acrobat.exe, AcroRd32.exe) spawning shells, scripting hosts (cmd.exe, powershell.exe, wscript.exe), or LOLBins shortly after opening a PDF
Unexpected child processes writing executables or scripts to user-writable directories such as %APPDATA%, %TEMP%, or ~/Library/Application Support
Crash telemetry or Windows Error Reporting entries referencing Acrobat modules with access violation exceptions during PDF parsing
Outbound network connections initiated by Acrobat processes to previously unseen domains or IPs

Detection Strategies

Correlate PDF open events with process lineage to flag Acrobat spawning interpreters, rundll32.exe, or regsvr32.exe
Alert on Acrobat processes performing memory allocation patterns or module loads that deviate from baseline
Inspect email gateway and web proxy logs for PDF attachments from external, low-reputation senders

Monitoring Recommendations

Enforce EDR telemetry collection on all endpoints running Acrobat or Acrobat Reader across Windows and macOS
Track Acrobat version inventory to identify hosts still running builds at or below 23.008.20470 (Continuous) and 20.005.30539 (Classic)
Retain PDF file hashes and email metadata for retrospective hunting once new indicators emerge

How to Mitigate CVE-2024-20727

Immediate Actions Required

Apply the updates listed in Adobe security bulletin APSB24-07 to all Acrobat and Acrobat Reader installations
Prioritize workstations that handle externally sourced PDFs, including help desk, finance, HR, and executive endpoints
Restrict PDF handling to the patched Acrobat build or an alternative reader on hosts that cannot update immediately
Reinforce user awareness that opening unsolicited PDF attachments can trigger code execution

Patch Information

Adobe released fixed versions for both the Continuous and Classic tracks in the Adobe Acrobat Security Advisory APSB24-07. Administrators should deploy the vendor-supplied installers through their standard software distribution tooling and verify version strings after deployment. Confirm that Adobe's auto-update service is enabled on endpoints that receive updates directly from the vendor.

Workarounds

Enable Acrobat's Protected View and Protected Mode to constrain PDF rendering inside a sandbox
Block or quarantine PDF attachments from external senders at the email gateway until patching completes
Disable JavaScript execution in Acrobat via Preferences > JavaScript to reduce exploit primitives
Apply application control policies that prevent Acrobat from spawning shells and scripting interpreters

bash

# Verify installed Acrobat Reader version on Windows
reg query "HKLM\SOFTWARE\Adobe\Acrobat Reader" /s /v "CurrentVersion"

# Disable JavaScript in Acrobat via registry (Windows, per-user hive)
reg add "HKCU\Software\Adobe\Adobe Acrobat\DC\JSPrefs" /v bEnableJS /t REG_DWORD /d 0 /f

# macOS: check installed Acrobat version
defaults read /Applications/Adobe\ Acrobat\ DC/Adobe\ Acrobat.app/Contents/Info CFBundleShortVersionString