CVE-2021-21057

Application crash via crafted PDF parsing

Published Feb 11, 2021 · Updated Sep 17, 2024

NULL pointer dereference in Adobe Acrobat Reader DC 2020.013.20074 and earlier allows attackers to crash the application via a crafted PDF file. During PDF parsing, the reader dereferences a null pointer reached through crafted file data; Adobe has not disclosed the responsible parser routine. A victim must open the malicious PDF, and exploitation runs in the current user's context, interrupting the application without reported code execution.

CVSS severity6.6
Medium
EPSS probability1.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in Adobe Acrobat Reader DC 2020.013.20074 and earlier allows attackers to crash the application via a crafted PDF file. During PDF parsing, the reader dereferences a null pointer reached through crafted file data; Adobe has not disclosed the responsible parser routine. A victim must open the malicious PDF, and exploitation runs in the current user's context, interrupting the application without reported code execution.

The record

CVE
CVE-2021-21057
Published
Feb 11, 2021
Updated
Sep 17, 2024
Vendor
Adobe
Product
Adobe Acrobat Reader
Classifications
CWE-476, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 11, 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 <=2017.011.30188
  2. Affected versionversion=unspecified <=2020.001.30018
  3. Affected versionversion=unspecified <=2020.013.20074
  4. Affected versionversion=unspecified <=None

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Adobe · Adobe Acrobat Readerversion=unspecified <=2017.011.30188; version=unspecified <=2020.001.30018; version=unspecified <=2020.013.20074; version=unspecified <=None

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
6.6Adobe Systems IncorporatedCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/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-476NULL Pointer Dereference
T1204.002User Execution: Malicious File

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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