CVE-2021-28554

Code execution via path parsing out-of-bounds read

Published Aug 24, 2021 · Updated Sep 16, 2024

Out-of-bounds read in Adobe Acrobat Reader DC 2021.001.20155 and earlier allows attackers to execute code through a malicious PDF. The path parser reads beyond an allocated buffer while processing crafted document data; Adobe has not published a finer-grained locus or malformed path structure. The flaw also affects Reader 2020 2020.001.30025 and earlier and Reader 2017 2017.011.30196 and earlier; execution requires a user to open the file and runs as that user.

CVSS severity7.8
High
EPSS probability46.03%
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 Acrobat Reader DC 2021.001.20155 and earlier allows attackers to execute code through a malicious PDF. The path parser reads beyond an allocated buffer while processing crafted document data; Adobe has not published a finer-grained locus or malformed path structure. The flaw also affects Reader 2020 2020.001.30025 and earlier and Reader 2017 2017.011.30196 and earlier; execution requires a user to open the file and runs as that user.

The record

CVE
CVE-2021-28554
Published
Aug 24, 2021
Updated
Sep 16, 2024
Vendor
Adobe
Product
Adobe Acrobat Reader
Classifications
CWE-125, T1204.002, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 24, 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 <=2017.011.30196
  2. Affected versionversion=unspecified <=2020.001.30025
  3. Affected versionversion=unspecified <=2021.001.20155
  4. Affected versionversion=unspecified <=None

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Adobe · Adobe Acrobat Readerversion=unspecified <=2017.011.30196; version=unspecified <=2020.001.30025; version=unspecified <=2021.001.20155; version=unspecified <=None

Published CVSS scores

6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
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.

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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