Actively exploited
Listed in CISA’s Known Exploited Vulnerabilities catalog since April 13, 2026.
CVE-2026-34621
Adobe Acrobat and Reader Prototype Pollution Vulnerability
Added to KEV April 13, 2026
Alert details
- Source feed
- CISA KEV
- CVE ID
- CVE-2026-34621
- CWE
- CWE-1321
- Affected products
- Acrobat and Reader · Adobe Acrobat and Reader · Adobe
What happened
Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution.
What it means for your business
Adobe Acrobat and Reader is listed in CISA's Known Exploited Vulnerabilities catalog (CVE-2026-34621). Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution. CISA remediation due date: 2026-04-27. If you need help checking exposure, call (864) 335-9223.
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
CISA due date: April 27, 2026
Sources
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