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

CISA Known Exploited Vulnerabilities

Name

Adobe Acrobat and Reader Prototype Pollution Vulnerability

Vendor

Adobe

Product

Acrobat and Reader

Added to the catalog

2026-04-13

Due date for US federal agencies

2026-04-27

Weaknesses

CWE-1321

Catalog version

2026.10.30

Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution.

Required action (CISA)

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Ransomware use: CISA does not mark known use of this vulnerability in ransomware campaigns.

Links in CISA's notes

• https://helpx.adobe.com/security/products/acrobat/apsb26-43.html
• https://nvd.nist.gov/vuln/detail/CVE-2026-34621

Read on 2026-11-02T23:39:54.475Z under licence cisa-kev-cc0@b0067899 from https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

NVD analysis

Status

Analyzed

Published

2026-04-11T07:16:03.633

Last modified

2026-10-26T21:10:00.170

Weaknesses

CWE-1321

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.

References

• 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)

This product uses the NVD API but is not endorsed or certified by the NVD.

Read on 2026-11-02T23:42:31.494Z under licence nvd-api-terms-of-use@ff2a5288 from https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34621

CVE record

Title (CNA)

Acrobat Reader | Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (CWE-1321)

Assigner

adobe

State

PUBLISHED

Published

2026-04-11T06:45:43.512Z

Updated

2026-08-27T22:15:48.961Z

Problem types

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') (CWE-1321)

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.

References

• https://helpx.adobe.com/security/products/acrobat/apsb26-43.html

Read on 2026-11-03T02:19:46.818Z under licence cve-terms-of-use@81bfa2f3 from https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34621.json

Defensive techniques (MITRE D3FEND)

D3FEND maps these defensive techniques to the weakness (CWE) that NVD lists for this CVE, through the digital artifacts the weakness affects. D3FEND does not say they stop this vulnerability.

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