CVE-2021-21088

Code execution via malicious PDF use-after-free

Published Sep 6, 2023 · Updated Aug 3, 2024

Use-after-free in Adobe Acrobat Reader DC 2020.013.20074 and earlier allows attackers to execute code through a malicious PDF. Adobe has not published the affected parser or the object-lifetime error that leaves freed memory accessible while the document is processed. A victim must open the crafted file, after which code runs with the victim's current-user privileges on Windows or macOS.

CVSS severity7.8
High
EPSS probability0.34%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Adobe Acrobat Reader DC 2020.013.20074 and earlier allows attackers to execute code through a malicious PDF. Adobe has not published the affected parser or the object-lifetime error that leaves freed memory accessible while the document is processed. A victim must open the crafted file, after which code runs with the victim's current-user privileges on Windows or macOS.

The record

CVE
CVE-2021-21088
Published
Sep 6, 2023
Updated
Aug 3, 2024
Vendor
Adobe
Product
Adobe Acrobat Reader
Classifications
CWE-416, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 6, 2023CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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 <=2017.011.30188

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Adobe · Adobe Acrobat Readerversion=0 <=2017.011.30188

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

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.

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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-416Use After Free
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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