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.

Overview

State: PUBLISHED
Assigner (CNA): adobe
CVSS severity: HIGH
CVSS score: 8.6 / 10
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Effective score: 8.6 / 10 HIGH source: CNA overview
CWE(s): CWE-1321
Reserved: 2026-03-30
Published: 2026-04-11 06:45 UTC
Last updated: 2026-04-14 03:55 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34621.json
Linked Threat: CVE-2026-34621 — Adobe Acrobat and Reader: Adobe Acrobat and Reader Prototype Pollution Vulnerability

CISA Known Exploited Vulnerabilities CISA KEV

CISA has confirmed in-the-wild exploitation of this CVE. Federal agencies must remediate by the due date below; private orgs should treat it as priority-1.

Vulnerability name: Adobe Acrobat and Reader Prototype Pollution Vulnerability
Vendor / project: Adobe
Product: Acrobat and Reader
Date added to KEV: 2026-04-13
Remediation due: 2026-04-27
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.
Ransomware campaign use: Unknown
CISA notes: https://helpx.adobe.com/security/products/acrobat/apsb26-43.html ; https://nvd.nist.gov/vuln/detail/CVE-2026-34621
CISA listing: www.cisa.gov/known-exploited-vulnerabilities-catalog

NVD triage scoring NVD CVE 2.0

Layer NVD adds on top of the CNA's CVE record — published / last-modified timestamps, exploitability / impact subscores, and the FIRST.org EPSS probability that this CVE will be exploited in the wild in the next 30 days.

NVD published: 2026-04-11 07:16:03 UTC
NVD last modified: 2026-04-13 21:23:27 UTC
NVD CVSS v3.1: 8.6 / 10 HIGH source: psirt@adobe.com
NVD CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Exploitability subscore: 1.8 / 10
Impact subscore: 6.0 / 10
EPSS score: 0.0981 (probability of exploitation in next 30 days)
EPSS percentile: 93.07% vs all CVEs — higher = more likely to be exploited, as of 2026-05-24

European Union Vulnerability Database ENISA EUVD

ENISA's official EU repository for curated vulnerability intelligence. Carries a separate identifier (EUVD-YYYY-NNNN) and frequently exposes an earlier-published description + CVSS than NVD does.

EUVD ID: EUVD-2026-21675
Assigner: adobe
Published: Apr 11, 2026, 6:45:43 AM
Updated: Apr 14, 2026, 3:55:27 AM
EUVD base score (CVSS 3.1): 8.6 / 10
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EUVD-reported EPSS: 9.8100
Vendors: Adobe
Products: Acrobat Reader (0 ≤26.001.21367)
Aliases: GHSA-vcqh-932g-m3qj

ENISA 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.

EUVD references (1)

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

Affected products (1)

Vendor	Product	Versions	Platforms
Adobe	Acrobat Reader	`0` (affected)	—

Affected products — CPE 2.3 (5) NVD

NVD's normalized CPE 2.3 matchers, used by vendor tools (vulnerability scanners, asset managers) for automated detection. Compare with the CNA's free-text "Affected products" section above.

cpe:2.3:a:adobe:acrobat_dc:*:*:*:*:continuous:*:*:*
cpe:2.3:a:adobe:acrobat_reader_dc:*:*:*:*:continuous:*:*:*
cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*
cpe:2.3:a:adobe:acrobat:*:*:*:*:classic:*:*:*

Vendor references (1)

References embedded in the original CVE record by the assigning CNA.

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

Web references (5)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

http://cwe.mitre.org/data/definitions/1321.html rapid7:cwe.mitre.org
https://attackerkb.com/topics/CVE-2026-34621 rapid7:attackerkb.com
https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-21675 rapid7:euvd.enisa.europa.eu
https://helpx.adobe.com/security/products/acrobat/apsb26-43.html rapid7:helpx.adobe.com
https://www.cve.org/CVERecord?id=CVE-2026-34621 rapid7:www.cve.org

NVD-tagged references (2)

Reference list NVD curates from the CNA record, vendor advisories, and third-party reports. The tag chips below are NVD's analyst-assigned categories.

https://helpx.adobe.com/security/products/acrobat/apsb26-43.html psirt@adobe.com Vendor Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34621 134c704f-9b21-4f2e-91b3-4a467353bcc0 US Government Resource

Indicators (2)

IOCs linked to the auto-promoted Threat row.

Type	Value	VirusTotal	Attached
cve	`CVE-2026-34621`	no local data	2026-05-14 02:58 UTC
cwe	`CWE-1321`	no local data	2026-05-14 02:58 UTC

Remediations (9)

Remediations are stored against the linked Threat row; the list below is deduplicated across both pages.

Critical Adobe Acrobat Vulnerability (CVE-2026-34621): Update Now to ...

web:www.tech2geek.net

Adobe fixes critical Acrobat flaw ( CVE-2026-34621 ) actively exploited. Update now to prevent remote code execution via malicious PDFs.

2026-05-14 09:18 UTC
Adobe Patches Actively Exploited Acrobat Reader Flaw CVE-2026-34621

web:thecyberexpress.com

Adobe issues emergency patch for Acrobat Reader flaw CVE-2026-34621 , a critical issue actively exploited in the wild enabling code execution risks.

2026-05-14 09:18 UTC
Adobe rolls out emergency fix for Acrobat, Reader zero-day flaw

web:www.bleepingcomputer.com

Adobe has released an emergency security update for Acrobat Reader to fix a vulnerability, tracked as CVE-2026-34621 , that has been exploited in zero-day attacks since at least December.

2026-05-14 09:18 UTC
Microsoft and Adobe Patch Tuesday, April 2026 Security Update Review

web:blog.qualys.com

With Qualys Policy Audit's out-of-the-box mitigation or Compensatory Controls, which reduce the risk of a vulnerability being exploited because the remediation ( fix / patch ) cannot be done immediately, these security controls are not recommended by any industry standards, such as CIS and DISA-STIG.

2026-05-14 09:18 UTC
Adobe Acrobat Zero-Day CVE-2026-34621 Under Active Attack

web:www.cyberkendra.com

Adobe confirms CVE-2026-34621 zero-day in Acrobat and Reader is being actively exploited. Windows and macOS users must update it.

2026-05-14 09:18 UTC
Adobe issues emergency fix for Acrobat Reader flaw exploited in the ...

web:www.helpnetsecurity.com

Adobe releases emergency security update for Adobe Acrobat Reader, patching a zero-day flaw ( CVE-2026-34621 ) exploited in the wild.

2026-05-14 09:18 UTC
April 2026 Patch Tuesday | Ivanti

web:www.ivanti.com

Adobe Acrobat ( CVE-2026-34621 ) and Google Chrome ( CVE - 2026 -5281) each had zero-day exploits leading up to Patch Tuesday. Ensure that you are prioritizing remediation of these two products to the latest version.

2026-05-14 09:18 UTC
Adobe brings Security Updates to tackle CVE-2026-34621 vulnerability

web:www.neowin.net

Adobe has brought in updates to fix a critical vulnerability that was allowing attackers to access users' system local files.

2026-05-14 09:18 UTC
CISA Required Action

CISA KEV

Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Due date: 2026-04-27 Known ransomware campaign use: Unknown

2026-05-14 01:13 UTC

AI Forensic Analysis

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-34621.json.

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