CVE-2021-21056

Arbitrary code execution via out-of-bounds PDF buffer read

Published Mar 12, 2021 · Updated Apr 23, 2025

Out-of-bounds read in Adobe FrameMaker 2020.0.1 and earlier allows remote attackers to execute code through a crafted PDF file. The PDF parser reads past the end of an allocated buffer when it processes crafted PDF data, allowing control of the current process. Exploitation requires the victim to open the file, and resulting code runs with the victim's privileges.

CVSS severity7.8
High
EPSS probability21.22%
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 read in Adobe FrameMaker 2020.0.1 and earlier allows remote attackers to execute code through a crafted PDF file. The PDF parser reads past the end of an allocated buffer when it processes crafted PDF data, allowing control of the current process. Exploitation requires the victim to open the file, and resulting code runs with the victim's privileges.

The record

CVE
CVE-2021-21056
Published
Mar 12, 2021
Updated
Apr 23, 2025
Vendor
Adobe
Product
Adobe FrameMaker
Classifications
CWE-125, T1204.002, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 12, 2021CVE 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=unspecified <=2020.0.1
  2. Affected versionversion=unspecified <=None

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Adobe · Adobe FrameMakerversion=unspecified <=2020.0.1; version=unspecified <=None

Published CVSS scores

9.3NIST NVDAV:N/AC:M/Au:N/C:C/I:C/A:C
7.8Adobe Systems IncorporatedCVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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-125Out-of-bounds Read
T1204.002Malicious 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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