CVE-2026-47961 Overview
CVE-2026-47961 is an out-of-bounds read vulnerability [CWE-125] affecting Adobe Acrobat Reader versions 24.001.30365, 26.001.21651, and earlier. The flaw allows an attacker to read memory outside the bounds of an allocated buffer, leading to disclosure of sensitive process memory. Successful exploitation requires user interaction, specifically that a victim opens a crafted malicious file. The vulnerability does not enable code execution or integrity impact, but the disclosed memory may contain pointers, tokens, or other data useful for chaining with additional exploits.
Critical Impact
An attacker can disclose sensitive memory contents from the Acrobat Reader process by tricking a user into opening a malicious PDF, potentially exposing data useful for bypassing mitigations or chaining further attacks.
Affected Products
- Adobe Acrobat Reader 24.001.30365
- Adobe Acrobat Reader 26.001.21651
- Adobe Acrobat Reader earlier versions
Discovery Timeline
- 2026-06-09 - CVE-2026-47961 published to NVD
- 2026-06-10 - Last updated in NVD database
Technical Details for CVE-2026-47961
Vulnerability Analysis
The vulnerability is an out-of-bounds read condition in Adobe Acrobat Reader's file parsing logic. When the application processes a crafted document, it reads beyond the boundary of an allocated buffer. The resulting data is returned through application code paths that may expose it to the attacker-controlled document context.
The impact profile shows confidentiality impact only, with no integrity or availability effects. This is consistent with a memory disclosure primitive rather than a corruption primitive. Attackers commonly use such primitives to defeat Address Space Layout Randomization (ASLR) or extract sensitive runtime data from the rendering process.
Exploitation is local and requires user interaction. The attack scope is unchanged, meaning the disclosed memory remains within the privilege boundary of the Acrobat Reader process.
Root Cause
The root cause is missing or incorrect bounds checking during parsing of a structure inside a PDF or related file format. The parser dereferences an offset or length field supplied by the malicious file without validating it against the size of the underlying buffer, resulting in an out-of-bounds read [CWE-125].
Attack Vector
The attack vector is local with user interaction required. An attacker delivers a malicious PDF through email, a website, a messaging platform, or shared storage. When the victim opens the file in a vulnerable version of Acrobat Reader, the crafted structure triggers the over-read. The leaked memory can be exfiltrated through JavaScript embedded in the document or through other channels available to PDF content.
No public proof-of-concept or in-the-wild exploitation has been reported. Refer to the Adobe Acrobat Security Advisory for vendor technical details.
Detection Methods for CVE-2026-47961
Indicators of Compromise
- PDF files originating from untrusted senders that contain unusual embedded JavaScript or malformed object streams.
- Acrobat Reader processes generating outbound network connections shortly after opening a document.
- Crashes or anomalous memory access patterns in AcroRd32.exe or Acrobat.exe recorded in Windows Error Reporting.
Detection Strategies
- Inspect inbound PDF attachments with sandbox detonation to surface malformed structures that trigger parser anomalies.
- Correlate Acrobat Reader version telemetry from endpoint inventory against the affected versions 24.001.30365 and 26.001.21651.
- Use endpoint identification rules that flag Acrobat Reader child processes spawning scripting interpreters or network utilities.
Monitoring Recommendations
- Monitor process telemetry for Acrobat Reader instances exhibiting unexpected outbound DNS or HTTP activity after document open events.
- Track email gateway logs for PDFs with high entropy embedded streams or obfuscated JavaScript.
- Audit endpoint software inventory weekly to confirm Acrobat Reader patch level across managed devices.
How to Mitigate CVE-2026-47961
Immediate Actions Required
- Apply the Adobe security update referenced in APSB26-63 to all endpoints running Acrobat Reader.
- Identify and prioritize patching for endpoints handling externally sourced PDF documents, such as legal, finance, and customer support workstations.
- Restrict execution of JavaScript within Acrobat Reader until patching is complete.
Patch Information
Adobe has published security guidance under bulletin APSB26-63. Administrators should upgrade Acrobat Reader to a version newer than 24.001.30365 and 26.001.21651 as listed in the Adobe Acrobat Security Advisory. Enterprise deployments should use Adobe's update channels or managed software distribution to enforce the patched build.
Workarounds
- Disable JavaScript in Acrobat Reader via Preferences > JavaScript > uncheck "Enable Acrobat JavaScript".
- Enable Protected View for files originating from the internet and other potentially unsafe locations.
- Configure email gateways to strip or quarantine PDFs from untrusted external senders pending review.
# Configuration example: Disable Acrobat JavaScript via Windows registry
reg add "HKCU\Software\Adobe\Acrobat Reader\DC\JSPrefs" /v bEnableJS /t REG_DWORD /d 0 /f
# Enforce Protected View for all files
reg add "HKCU\Software\Adobe\Acrobat Reader\DC\TrustManager" /v iProtectedView /t REG_DWORD /d 2 /f
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
