Vulnerability · CVE-2026-34621
Adobe Acrobat and Reader Prototype Pollution Vulnerability
Published Apr 7, 2026 · catalog updated Aug 28, 2026 · Adobe Acrobat and Reader
Patch now
CVE-2026-34621 is in the CISA known-exploited catalog, due Apr 27, 2026. Confirm Adobe Acrobat and Reader against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Gaps on this record
- No version range is stored. A customer cannot check an installed version against this record.
- Severity
- High8.6
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 2.18%
- Remediation
- Remediation guidance
- Affected products
- cpe adobe/acrobat · cpe adobe/acrobat dc · cpe adobe/acrobat reader dc · vendor Adobe Acrobat and Reader
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.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe adobe/acrobatversion unspecified
- cpe adobe/acrobat dcversion unspecified
- cpe adobe/acrobat reader dcversion unspecified
- vendor Adobe Acrobat and Readerversion unspecified
How to fix CVE-2026-34621
Recommended remediation
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. CISA due date Apr 27, 2026.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2026-34621 is in the CISA known-exploited catalog, due Apr 27, 2026. Confirm Adobe Acrobat and Reader against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Affected version ranges are not on this record. Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
What should an analyst verify?
CWE-1321: Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). EPSS 2.18%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Apr 11, 2026 · Catalog
Detected
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.
Apr 13, 2026 · CISA KEV
Known exploited
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Apr 27, 2026 · CISA KEV
Remediation due
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Aug 27, 2026 · Catalog
Updated
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.
Aug 28, 2026 · NIST NVD
Updated
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.
Sources
- CISA KEVConfirmed exploitationCVE-2026-34621
Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution.
cisa.gov - CVE.orgVulnerability recordCVE-2026-34621
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2026-34621
30-day exploitation probability 2.2%
first.org - NIST NVDVulnerability recordCVE-2026-34621
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
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-2026-34621
Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution.
vulncheck.com
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.