CVE-2021-39820

Arbitrary code execution via malicious TIFF out-of-bounds write

Published Jun 15, 2022 · Updated Apr 23, 2025

Out-of-bounds write in Adobe InDesign allows attackers to execute code in the current user's context via a malicious TIFF file. InDesign's TIFF-processing path writes beyond a buffer boundary while handling crafted image data, but Adobe has not disclosed the responsible function or malformed field. A user must open or otherwise process the file; successful exploitation runs attacker-controlled code with that user's privileges.

CVSS severity7.8
High
EPSS probability3.67%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in Adobe InDesign allows attackers to execute code in the current user's context via a malicious TIFF file. InDesign's TIFF-processing path writes beyond a buffer boundary while handling crafted image data, but Adobe has not disclosed the responsible function or malformed field. A user must open or otherwise process the file; successful exploitation runs attacker-controlled code with that user's privileges.

The record

CVE
CVE-2021-39820
Published
Jun 15, 2022
Updated
Apr 23, 2025
Vendor
Adobe
Product
InDesign
Classifications
CWE-787, T1204.002, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 15, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=16.3.2

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Adobe · InDesignversion=0 <=16.3.2

Published CVSS scores

7.8Adobe Systems IncorporatedCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1204.002User Execution: Malicious File
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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