Actively exploited

CVE-2023-21608 Adobe Acrobat and Reader Use-After-Free Vulnerability

Adobe Acrobat and Reader contains a use-after-free vulnerability that allows for code execution in the context of the current user.

From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.

Our Assessment

Should You Worry?

Patch urgentlyCybergen assessment
  • CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 10 Oct 2023.
  • Rated High severity (CVSS 7.8, scored by Vendor).
  • It has been in the catalogue for 1,123 days. Systems still unpatched now have almost certainly been scanned for it.
The Vulnerability

What It Is

Adobe Acrobat Reader versions 22.003.20282 (and earlier), 22.003.20281 (and earlier) and 20.005.30418 (and earlier) are affected by a Use After Free vulnerability that could result in 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.

Affected Versions

ProductVersions
Adobe Acrobat Readerunspecified to 20.005.30418
unspecified to 22.003.20282
unspecified to 22.003.20281
unspecified to None

From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.

From Watch to Action

What To Do Now

  1. 1

    Find it

    Search your asset inventory and external attack surface for Adobe Acrobat and Reader. Include cloud images, appliances and anything a supplier runs for you.

    Attack Surface Management
  2. 2

    Fix it

    Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

    Vulnerability Management
  3. 3

    Hunt for compromise

    If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.

    Incident Response
  4. 4

    Prove it is fixed

    Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.

    Penetration Testing

Not Sure If You Are Exposed?

Our attack surface and vulnerability teams can check your internet-facing estate for CVE-2023-21608 and every other exploited flaw on the list.

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