CVE-2021-40724Public exploit

Code execution via unsanitized download path

Published Oct 15, 2021 · Updated Sep 17, 2024

Path traversal in Adobe Acrobat Reader for Android 21.8.0 and earlier allows attackers to execute code via a malicious file. ARURLFileDownloadAsyncTask uses a decoded URL path segment without sanitizing it before file creation, allowing a native library write into Play Core storage. A victim must open the malicious file; the planted library loads when the Fill & Sign feature is used and runs as the current user.

CVSS severity7.8
High
EPSS probability3.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Path traversal in Adobe Acrobat Reader for Android 21.8.0 and earlier allows attackers to execute code via a malicious file. ARURLFileDownloadAsyncTask uses a decoded URL path segment without sanitizing it before file creation, allowing a native library write into Play Core storage. A victim must open the malicious file; the planted library loads when the Fill & Sign feature is used and runs as the current user.

The record

CVE
CVE-2021-40724
Published
Oct 15, 2021
Updated
Sep 17, 2024
Vendor
Adobe
Product
Adobe Acrobat Reader
Classifications
CWE-22, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 15, 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

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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 <=21.8.0
  2. Affected versionversion=unspecified <=None

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Adobe · Adobe Acrobat Readerversion=unspecified <=21.8.0; version=unspecified <=None

Published CVSS scores

6.8NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
7.8AdobeCVSS: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 exploitPublished

Weakness, pattern, technique

CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
T1204.002Malicious File

Public exploit references

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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