CVEs / CVE-2026-34621
CVE-2026-34621: Adobe Acrobat and Reader Prototype Pollution Vulnerability
- Known exploited in the CISA KEV catalog since 13 Apr 2026
- high 8.6 CVSS 3.1 (from the CNA)
- EPSS 7.23% chance of exploitation in the next 30 days, higher than 94% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution.
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.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Adobe Acrobat DC | up to and including 26.001.21367 | — |
| Adobe Acrobat Reader DC | up to and including 26.001.21367 | — |
| Adobe Acrobat 2024 | up to and including 24.001.30356 | — |
Exploitation
| In CISA KEV since | 13 Apr 2026 |
|---|---|
| Due date for US federal agencies | 27 Apr 2026 |
| Used in ransomware campaigns | Unknown |
| 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. |
Severity
| CVSS 3.1 | 8.6 highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-1321 |
References
- CVE-2026-34621 on NVD
- CVE-2026-34621 in the CISA KEV catalog
- https://helpx.adobe.com/security/products/acrobat/apsb26-43.html (cited by CISA)
- https://helpx.adobe.com/security/products/acrobat/apsb26-43.html Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34621 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.