# CVE-2026-34621: Adobe Acrobat and Reader Prototype Pollution Vulnerability

CVE-2026-34621 is fixed in 2 products on 1 platform, first by Adobe Acrobat Reader DC 26.001.21411, released April 10, 2026. It is being exploited: CISA added it to the Known Exploited Vulnerabilities catalog on April 13, 2026. Patch Radar priority: Patch now.

- Web page: https://patchblox.com/security/cve/CVE-2026-34621
- Priority: Patch now
- CVSS: 8.6
- EPSS: 0.0734
- CISA KEV: listed Apr 13, 2026, federal due date Apr 27, 2026
- Exploited (vendor report): yes
- Publicly disclosed: no
- Published: Apr 11, 2026
- Weakness: CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (CWE-1321)
- Vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-34621

## Description

Acrobat Reader versions 24.001.30356, 26.001.21367 and earlier are affected by an Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') 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.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Windows apps | Adobe Acrobat Reader DC | 26.001.21411 | [Adobe Acrobat Reader DC 26.001.21411](https://patchblox.com/security/data/fix/windows-app/adobe.acrobat.reader.32-bit-26.001.21411.md) | Apr 10, 2026 |
| Windows apps | Adobe Acrobat Reader DC (64-bit) | 26.001.21411 | [Adobe Acrobat Reader DC (64-bit) 26.001.21411](https://patchblox.com/security/data/fix/windows-app/adobe.acrobat.reader.64-bit-26.001.21411.md) | Apr 10, 2026 |

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Data as of 2026-11-09T07:25:28Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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