dbcve.org
Acrobat DcApplication · Adobe

CVE-2021-44740

MEDIUM · 5.5 CVSS v3.1 Published 2022-01-14
Fix available
A fix is available. Upgrade to after 21.007.20099 or later.
See remediation →
58/100
Remediation priority · Elevated
No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Acrobat Reader DC version 21.007.20099 (and earlier), 20.004.30017 (and earlier) and 17.011.30204 (and earlier) are affected by a Null pointer dereference vulnerability when parsing a specially crafted file. An unauthenticated attacker could leverage this vulnerability to achieve an application denial-of-service in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Adobe Acrobat Reader DC contains a null pointer dereference vulnerability when parsing specially crafted PDF files. An unauthenticated attacker can cause the application to crash by enticing a user to open a malicious PDF, resulting in denial-of-service in the current user context. The vulnerability affects three major version branches (21.x, 20.x, and 17.x) and requires user interaction for exploitation.

MitigationUpdate Adobe Acrobat Reader DC to the latest version (21.007.20099+, 20.004.30017+, or 17.011.30204+) to remediate this vulnerability. Until updated, exercise caution when opening PDF files from untrusted sources.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Acrobat DcApplication
Affected:>= 15.008.20082, <= 21.007.20099
Acrobat Reader DcApplication
Affected:>= 15.008.20082, <= 21.007.20099
AcrobatApplication
Affected:>= 17.011.30059, <= 17.011.30204>= 20.001.30005, <= 20.004.30017
Acrobat ReaderApplication
Affected:>= 17.011.30059, <= 17.011.30204>= 20.001.30005, <= 20.004.30017

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the installed Adobe product
    Open Adobe Acrobat or Reader, then go to Help > About Adobe Acrobat (or Reader) to display the version information dialog box showing the exact version number
    Affected if The product name shows Adobe Acrobat Reader DC, Adobe Acrobat DC, Adobe Acrobat, or Adobe Reader
  2. Record the exact version number
    Note the full version number displayed in the About dialog (for example: 21.001.20135 or 20.004.30006)
    Affected if A full version number is visible showing a build like 21.x, 20.x, or 17.x within the 15.x through 21.x range
  3. Compare your version against CVE-2021-44740 affected ranges
    Check if your installed version falls within: 15.008.20082 to 21.007.20099 (DC branch); 20.001.30005 to 20.004.30017 (Acrobat 20.x); or 17.011.30059 to 17.011.30204 (Acrobat 17.x)
    Affected if Your version number is equal to or greater than 15.008.20082 AND equal to or less than 21.007.20099, OR falls within 20.001.30005-20.004.30017, OR falls within 17.011.30059-17.011.30204
  4. Confirm PDF functionality is enabled
    Verify the application can open and render PDF files normally (try opening any standard PDF document)
    Affected if PDF files open successfully, indicating the vulnerable parsing component is active and usable
  5. Determine user interaction exposure
    Assess whether the system receives PDF files from external or untrusted sources (email attachments, downloaded files, network shares)
    Affected if Users on this system routinely open PDF files from external or untrusted sources, enabling the attack vector

You are affected if your installed Adobe Acrobat or Reader version falls within the listed version ranges AND users on this system open PDF files from any source, since the vulnerability triggers upon opening a specially crafted PDF.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to a release after 21.007.20099
Interim mitigation

Update Adobe Acrobat Reader DC to the latest version (21.007.20099+, 20.004.30017+, or 17.011.30204+) to remediate this vulnerability. Until updated, exercise caution when opening PDF files from untrusted sources.

Recommended fix Moderate confidence

Acrobat DC/Reader DC: 21.008.20092+ (continuous) or 20.005.30013+ (classic 2020); Acrobat/Reader 2017: 17.012.20093+

  1. 1. Verify current Adobe Acrobat or Reader version by opening the application and navigating to Help > About Adobe Acrobat/Reader
  2. 2. For Acrobat DC/Reader DC (continuous track): Upgrade to version 21.008.20092 or later
  3. 3. For Acrobat DC/Reader DC (classic 2020 track): Upgrade to version 20.005.30013 or later
  4. 4. For Acrobat/Reader 2017 (classic track): Upgrade to version 17.012.20093 or later
  5. 5. Download the appropriate updated version from the official Adobe download page at get.adobe.com/reader or get.adobe.com/acrobat
  6. 6. Close all Adobe applications before running the installer
  7. 7. Install the updated version and restart the application
  8. 8. Verify the installed version matches or exceeds the fixed versions listed above
Caveat Standard Adobe update with no expected breaking changes; this is a security patch release

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Acrobat Dc Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing1.0 h
  • Review / QA1.0 h
5.0 hours of engineering $890
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,424.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-44740 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-44740 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data