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Findings

CVE-2021-28550

Adobe Acrobat and Reader Use-After-Free Vulnerability

Published Sep 2, 2021 · corrected/updated Jun 16, 2026 · adobe acrobat dc · evidence confidence very high

Acrobat Reader DC versions versions 2021.001.20150 (and earlier), 2020.001.30020 (and earlier) and 2017.011.30194 (and earlier) are affected by a Use After Free vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2021-28550 is a high public vulnerability record for adobe acrobat dc. CISA lists it as known exploited. Published remediation guidance: Apply updates per vendor instructions. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether adobe acrobat dc is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: adobe/acrobat; adobe/acrobat dc; adobe/acrobat reader; adobe/acrobat reader dc. Published remediation guidance: Apply updates per vendor instructions. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: CVSS 8.8, EPSS 51.9%. CISA lists it as known exploited. Weakness classes: CWE-416. Sources contributing to this record: cisa_kev, cve_org, epss, nvd. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Confirmed in CISA KEV since Nov 3, 2021. Listed in the CISA Known Exploited Vulnerabilities catalog.

  • Patch and remediation

    Apply updates per vendor instructions. CISA due date Nov 17, 2021.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Sep 2, 2021 · Catalog

    Detected

    Acrobat Reader DC versions versions 2021.001.20150 (and earlier), 2020.001.30020 (and earlier) and 2017.011.30194 (and earlier) are affected by a Use After Free vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a maliciou

  2. Nov 3, 2021 · CISA KEV

    Known exploited

    Apply updates per vendor instructions.

  3. Nov 17, 2021 · CISA KEV

    Remediation due

    Apply updates per vendor instructions.

  4. Jun 16, 2026 · Catalog

    Updated

    Acrobat Reader DC versions versions 2021.001.20150 (and earlier), 2020.001.30020 (and earlier) and 2017.011.30194 (and earlier) are affected by a Use After Free vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a maliciou

Affected

  • cpe adobe/acrobatversion unspecified
  • cpe adobe/acrobat dcversion unspecified
  • cpe adobe/acrobat readerversion unspecified
  • cpe adobe/acrobat reader dcversion unspecified
  • vendor Adobe Acrobat and Readerversion unspecified

Sources

  • CISA KEVConfirmed exploitationCVE-2021-28550

    Adobe Acrobat and Reader contains a use-after-free vulnerability that could allow an unauthenticated attacker to achieve code execution in the context of the current user.

    cisa.gov
  • CVE.orgVulnerability recordCVE-2021-28550

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2021-28550

    30-day exploitation probability 51.9%

    first.org
  • NIST NVDVulnerability recordCVE-2021-28550

    Acrobat Reader DC versions versions 2021.001.20150 (and earlier), 2020.001.30020 (and earlier) and 2017.011.30194 (and earlier) are affected by a Use After Free vulnerability. An unauthenticated attacker could leverage this vulnerability to achieve arbitrary code execution in the

    nvd.nist.gov

References