CVE-2026-34705 Overview
CVE-2026-34705 is an out-of-bounds read vulnerability in Adobe InDesign Desktop versions 21.3, 20.5.3, and earlier. The flaw [CWE-125] allows an attacker to read memory outside allocated buffers, leading to disclosure of sensitive information from the application process. Exploitation requires a victim to open a malicious file crafted by the attacker. The vulnerability impacts InDesign installations on Microsoft Windows and Apple macOS. Adobe addressed the issue in security advisory APSB26-58.
Critical Impact
Successful exploitation discloses sensitive memory contents from the InDesign process, which could expose data useful for chaining with additional vulnerabilities or bypassing memory protections.
Affected Products
- Adobe InDesign Desktop 21.3 and earlier 21.x versions
- Adobe InDesign Desktop 20.5.3 and earlier 20.x versions
- Apple macOS and Microsoft Windows installations of the affected InDesign builds
Discovery Timeline
- 2026-06-09 - CVE-2026-34705 published to NVD
- 2026-06-10 - Last updated in NVD database
Technical Details for CVE-2026-34705
Vulnerability Analysis
The vulnerability is an out-of-bounds read in Adobe InDesign's file parsing logic. When InDesign processes a malformed document, the parser reads memory past the bounds of an allocated buffer. This out-of-bounds access returns adjacent heap or stack memory to the application's processing context. An attacker controlling the malicious file can position the read to leak sensitive memory contents. The vulnerability is local with user interaction required, since the victim must open the attacker-supplied file. Confidentiality impact is high, while integrity and availability are unaffected.
Root Cause
The defect [CWE-125] stems from missing or incorrect bounds checking when InDesign parses fields within a document file format. The parser trusts length or offset values embedded in the file without validating them against the actual allocated buffer size. Crafted values cause read operations to extend beyond the buffer boundary into adjacent memory regions.
Attack Vector
An attacker creates a malicious InDesign document containing manipulated structures that trigger the out-of-bounds read. The attacker delivers the file through email, file sharing services, or a website. When the victim opens the file in a vulnerable InDesign version, the parser reads sensitive memory. The leaked data can be exfiltrated through embedded objects, error messages, or rendered content within the document.
No public proof-of-concept code is available for CVE-2026-34705. Refer to the Adobe Security Advisory APSB26-58 for vendor technical details.
Detection Methods for CVE-2026-34705
Indicators of Compromise
- InDesign document files (.indd, .indt, .idml) received from untrusted sources or with anomalous internal structures
- InDesign process crashes or unexpected exceptions during document open operations
- Outbound network connections initiated by InDesign.exe shortly after opening a document
Detection Strategies
- Inspect inbound email attachments and file shares for InDesign document types and quarantine those from unverified senders
- Monitor endpoint telemetry for InDesign child processes, unusual file reads, or memory access violations during document parsing
- Correlate user-initiated file opens of InDesign documents with subsequent suspicious process or network activity
Monitoring Recommendations
- Log InDesign application version inventory across endpoints to identify systems still running vulnerable builds
- Alert on InDesign processes spawning command interpreters, scripting hosts, or making outbound HTTP/HTTPS connections
- Track document file origins using mark-of-the-web attributes on Windows endpoints
How to Mitigate CVE-2026-34705
Immediate Actions Required
- Update Adobe InDesign Desktop to the fixed versions identified in Adobe Security Advisory APSB26-58
- Inventory all macOS and Windows endpoints running InDesign 21.3, 20.5.3, or earlier and prioritize patching
- Warn users to avoid opening InDesign files received from untrusted or unexpected sources
Patch Information
Adobe published security advisory APSB26-58 with updated InDesign Desktop builds that remediate the out-of-bounds read. Apply the vendor-supplied updates through the Adobe Creative Cloud desktop application or through enterprise deployment tooling. See the Adobe Security Advisory APSB26-58 for exact fixed version numbers and download instructions.
Workarounds
- Restrict opening of InDesign documents to files originating from trusted, internal sources until patches are applied
- Apply application allowlisting and least-privilege user accounts to limit the impact of process memory disclosure
- Use protected-view or sandboxed file handling workflows for externally sourced design assets
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
