Exploited vulnerabilities / CVE-2026-34621
Confirmed exploited · remote code execution · Adobe Acrobat and ReaderCVE-2026-34621
Adobe Acrobat and Reader remote code execution, confirmed exploited in the wild.
Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution.
| CISA's name for it | Adobe Acrobat and Reader Prototype Pollution Vulnerability |
|---|---|
| Vendor and product | Adobe · Acrobat and Reader |
| Type | remote code execution · CWE-1321 |
| Exploited | Confirmed by CISA listed 13 April 2026 |
| Likelihood | more likely to be exploited than most |
| Deadline | 27 April 2026 · already passed |
| Used in ransomware | Not reported |
| Advisories | helpx.adobe.com ↗ · nvd.nist.gov ↗ |
Three steps, in this order
Patch to the fixed version the vendor names, today if the product faces the internet.
Until it is patched, take the affected service off the internet or put it behind a VPN or allow-list.
Look for signs it was already used: new accounts, web shells, unexpected processes and outbound connections since the date it was listed.
| CISA's 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. |
|---|
Know before someone else finds it
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CVE-2026-34621 in short
Is CVE-2026-34621 being exploited?
Yes. CISA added CVE-2026-34621 to its Known Exploited Vulnerabilities catalogue on 13 April 2026, which it does only on evidence of exploitation in the wild.
What is the CISA deadline for CVE-2026-34621?
US federal agencies must remediate it by 27 April 2026. Everyone else should treat that date as the latest safe point to patch an internet-facing system.
How likely is CVE-2026-34621 to be exploited in the next 30 days?
FIRST's Exploit Prediction Scoring System gives it 7.3%, the 94th percentile of every CVE it scores.
How do I fix CVE-2026-34621?
Patch to the fixed version the vendor names, today if the product faces the internet. Until it is patched, take the affected service off the internet or put it behind a VPN or allow-list. Look for signs it was already used: new accounts, web shells, unexpected processes and outbound connections since the date it was listed.
Other Adobe vulnerabilities being exploited
| CVE | Product | Type | Listed |
|---|---|---|---|
| CVE-2026-48356 | Commerce and Magento | remote code execution | 27 October 2026 |
| CVE-2026-71362 | Commerce and Magento | exploited vulnerability | 24 September 2026 |
| CVE-2026-75650 | Commerce and Magento | remote code execution | 8 September 2026 |
| CVE-2026-48282 | ColdFusion | remote code execution | 7 July 2026 |
| CVE-2009-3459 | Acrobat and Reader | remote code execution | 20 May 2026 |
| CVE-2020-9715 | Acrobat | remote code execution | 13 April 2026 |
Sources: CISA Known Exploited Vulnerabilities catalogue (released 10 November 2026) and FIRST EPSS. Page compiled automatically by SAK T.L.M, the threat-intelligence tool of SAK T.E.C, on 13 November 2026.