Adobe Acrobat and Reader Use-After-Free Vulnerability
What it is
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.
Who's affected
Affects anyone opening, editing, or signing PDFs in Adobe Acrobat or Reader. For a CPA or legal practice, PDFs are typically client tax returns, engagement letters, signed agreements, and discovery documents — opening a malicious PDF runs attacker code in the user's session, which can pivot to file shares or email.
What to do
Apply updates per vendor instructions.
CISA action deadline: November 17, 2021. Federal agencies must complete the required action by this date. For private SMBs the deadline is advisory — but treat it as a strong recommendation, especially if you handle regulated data (HIPAA, GLBA, ABA model rules).
If you don't have someone in-house to verify the patch deployed across every endpoint — or you're not sure whether you're affected — that's exactly the kind of triage we do. Book a free 20-minute triage call.
Severity
CVSS base score: 8.8 — HIGH
Weakness classification: CWE-416
Source
Pulled daily from the public cisagov/kev-data mirror (CC0). View the original entry on cisa.gov. CISA KEV is US-Government public-domain data; we add the SMB-vertical framing and the coping action above.