CVE-2021-28562Network attack vector

Code execution via JavaScript search-query use-after-free

Published Jun 28, 2021 · Updated Sep 16, 2024

Use after free in Adobe Acrobat Reader allows remote attackers to execute code as the current user through a malicious PDF. The flaw occurs while JavaScript executes search queries, but Adobe has not published the responsible function or invalid object-lifetime operation. Exploitation requires a victim to open the malicious file; successful code runs with that user's privileges on affected Windows and macOS installations.

CVSS severity8.8
High
EPSS probability5.12%
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 allows remote attackers to execute code as the current user through a malicious PDF. The flaw occurs while JavaScript executes search queries, but Adobe has not published the responsible function or invalid object-lifetime operation. Exploitation requires a victim to open the malicious file; successful code runs with that user's privileges on affected Windows and macOS installations.

The record

CVE
CVE-2021-28562
Published
Jun 28, 2021
Updated
Sep 16, 2024
Vendor
Adobe
Product
Adobe Acrobat Reader
Classifications
CWE-416, T1204.002, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 28, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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=unspecified <=2017.011.30194
  2. Affected versionversion=unspecified <=2020.001.30020
  3. Affected versionversion=unspecified <=2021.001.20150
  4. Affected versionversion=unspecified <=None

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Adobe · Adobe Acrobat Readerversion=unspecified <=2017.011.30194; version=unspecified <=2020.001.30020; version=unspecified <=2021.001.20150; version=unspecified <=None

Published CVSS scores

8.8Adobe Systems IncorporatedCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST National Vulnerability DatabaseAV: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)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
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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