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IndesignApplication · Adobe

CVE-2026-21278

MEDIUM · 5.5 CVSS v3.1 Published 2026-01-13
Fix available
A fix is available. Upgrade to 20.5.1 / 21.1 or later.
See remediation →
58/100
Remediation priority · Elevated
No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
InDesign Desktop versions 21.0, 19.5.5 and earlier are affected by an Out-of-bounds Read vulnerability that could lead to memory exposure. An attacker could leverage this vulnerability to access sensitive information stored in memory. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Adobe InDesign Desktop versions 21.0, 19.5.5 and earlier contain an out-of-bounds read vulnerability that can be triggered when a user opens a maliciously crafted file. This allows memory exposure and potential access to sensitive data stored in process memory.

MitigationApply the vendor-supplied patch from Adobe when available. Until then, enforce user awareness to avoid opening untrusted InDesign files and consider endpoint protection that can detect malicious document files.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
IndesignApplication
Affected:< 20.5.1>= 21.0, < 21.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Find installed InDesign version
    Check the application version through the About dialog (Help > About Adobe InDesign) or via the Windows Registry at HKEY_LOCAL_MACHINE\SOFTWARE\Adobe\InDesign\InstallVersion, or on Mac inspect /Applications/Adobe InDesign*/Adobe InDesign*.app/Contents/Info.plist for CFBundleShortVersionString
    Affected if The installed version is 21.0, or 19.5.5 or earlier, or falls between 21.0 (inclusive) and 21.1 (exclusive), or is below 20.5.1 (excluding 19.5.6 through 20.x which may not be listed)
  2. Confirm InDesign is used to open document files
    Verify the application is configured to handle .indd files by checking file associations or simply note that InDesign can open .indd files as its primary function
    Affected if InDesign is installed and capable of opening .indd files, which is the default configuration for the software
  3. Verify the vulnerable code path exists
    This vulnerability is triggered when a user opens a maliciously crafted .indd file; the out-of-bounds read occurs in the file parsing functionality that handles the document structure
    Affected if The InDesign installation has not been patched and runs an affected version - the vulnerable file parsing code is present in the unpatched software

You are affected if your installed Adobe InDesign version is 21.0, or 19.5.5 and earlier, or any version from 21.0 up to but not including 21.1, or below 20.5.1 - the vulnerability triggers when opening a specially crafted .indd file.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 20.5.1 / 21.1 or later
Fixed in 20.5.121.1
Interim mitigation

Apply the vendor-supplied patch from Adobe when available. Until then, enforce user awareness to avoid opening untrusted InDesign files and consider endpoint protection that can detect malicious document files.

Recommended fix High confidence

InDesign 20.5.1 or later (for versions before 20.5.1); InDesign 21.1 or later (for version 21.0)

  1. 1. Close all running instances of Adobe InDesign
  2. 2. Back up any important InDesign documents and settings
  3. 3. Download the latest version of Adobe InDesign from the official Adobe website (helpx.adobe.com) or through the Creative Cloud desktop application
  4. 4. Run the installer and follow the on-screen prompts to complete the upgrade
  5. 5. After installation, verify the version by opening InDesign and checking Help > About InDesign
  6. 6. Confirm the installed version is either 20.5.1 or higher, or 21.1 or higher
  7. 7. Test that existing documents open correctly in the updated version
Caveat Minor: Some legacy document features or third-party plug-ins may behave differently; always test critical workflows with a backup copy before production use

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Indesign Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $890
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-21278 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data