CVE-2021-28559Network attack vector

Restricted data disclosure from global variables and objects

Published Sep 2, 2021 · Updated Sep 17, 2024

Information exposure in affected Adobe Acrobat Reader releases allows remote attackers to read restricted data from global variables and objects. Adobe has not disclosed the responsible code path or the unsafe operation that exposes those process-scoped values. No authentication or user interaction is required, and the published record identifies no integrity or availability consequence.

CVSS severity5.3
Medium
EPSS probability1.65%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information exposure in affected Adobe Acrobat Reader releases allows remote attackers to read restricted data from global variables and objects. Adobe has not disclosed the responsible code path or the unsafe operation that exposes those process-scoped values. No authentication or user interaction is required, and the published record identifies no integrity or availability consequence.

The record

CVE
CVE-2021-28559
Published
Sep 2, 2021
Updated
Sep 17, 2024
Vendor
Adobe
Product
Adobe Acrobat Reader
Classifications
CWE-359
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 2, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

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

5.3Adobe Systems IncorporatedCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.0NIST National Vulnerability DatabaseAV:N/AC:L/Au:N/C:P/I:N/A:N

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-359Exposure of Private Personal Information to an Unauthorized Actor

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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