CVE-2021-21045

Local privilege escalation through installer access control

Published Feb 11, 2021 · Updated Sep 16, 2024

Improper access control in affected Adobe Acrobat and Reader releases allows local users to elevate privileges in the current user's context. Adobe identifies the installer as the affected area but has not published the component, file, or access-control operation that fails. Exploitation requires low local privileges and user interaction; successful use crosses a security boundary and gains the current user's privileges.

CVSS severity8.2
High
EPSS probability1.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in affected Adobe Acrobat and Reader releases allows local users to elevate privileges in the current user's context. Adobe identifies the installer as the affected area but has not published the component, file, or access-control operation that fails. Exploitation requires low local privileges and user interaction; successful use crosses a security boundary and gains the current user's privileges.

The record

CVE
CVE-2021-21045
Published
Feb 11, 2021
Updated
Sep 16, 2024
Vendor
Adobe
Product
Adobe Acrobat 2020
Classifications
T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 11, 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=20.0 <=20.001.30018

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Adobe · Adobe Acrobat 2020version=20.0 <=20.001.30018
Adobe · Adobe Acrobat Reader 2020version=20.0 <=20.001.30018
Adobe · Adobe Acrobat DCversion=0 <20.013.20074
Adobe · Adobe Acrobat Reader 2017version=17.0 <=17.011.30188
Adobe · Adobe Acrobat Reader DCversion=0 <=20.013.20074
Adobe · Adobe Acrobat Readerversion=unspecified <=2017.011.30188; version=unspecified <=2020.001.30018; version=unspecified <=2020.013.20074; version=unspecified <=None
Adobe · Adobe Acrobat 2017version=17.0 <=17.011.30188

Published CVSS scores

8.2Adobe Systems IncorporatedCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H
9.3NIST NVDAV:N/AC:M/Au:N/C:C/I:C/A:C

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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1068Exploitation for Privilege Escalation

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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