CVE-2026-34621
Adobe — Adobe Acrobat and Reader Prototype Pollution Vulnerability
Adobe · CWE-1321 · in CISA KEV since 2026-04-13
EVRS 75 of 100 Urgent
Patch This Cycle
Rank 1,227 of 2,960 tracked
Raised to the floor for a confirmed exploited vulnerability.
Why it scores 75
Evidence available: 6 of 7 signalsListed in the CISA KEV catalog, and an EPSS probability of 0.022.
- CISA KEVApplied
- RansomwareDid not apply
- Vendor exploitationDid not apply
- EPSSApplied
- Microsoft Exploitability IndexNot applicable
- Pre-patch disclosureNo data
- KEV recencyDid not apply
- CVSSApplied
The band answers “how soon”, not “how bad”. No data for: Pre-patch disclosure. Why some signals show no data
Fix
Patch or fixed version identifiedCISA required action
Fixed in
acrobat dc: update to 26.001.21411 or later | acrobat reader dc: update to 26.001.21411 or later | acrobat: update to 24.001.30362 or later | acrobat: update to 24.001.30360 or later
Affected versions
- acrobat dc
< 26.001.21411 - acrobat reader dc
< 26.001.21411 - acrobat
>= 24.0.0 < 24.001.30362>= 24.0.0 < 24.001.30360 - macos
- windows
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.
Fixed versions from NVD.
Evidence
Each value with its source| Measure | Value | Source |
|---|---|---|
| CVSS base scoreHow severe the flaw is in itself. It does not say how likely an attack is. | 8.6 | NVD |
| FIRST EPSSFIRST's estimate of the chance this is exploited in the next 30 days, and how that ranks against all CVEs. | 0.022 (82.2nd pctl) | FIRST EPSS |
| Actively exploitedWhether a source of record has confirmed attacks using it in the wild. | Confirmed | CISA KEV |
| Ransomware campaign useWhether CISA has seen ransomware operators use it. | Unknown or none | CISA KEV |
| CISA remediation deadlineThe date US federal agencies must have fixed or mitigated it. | 2026-04-27 · CISA federal deadline · Overdue by 6 months | CISA KEV |
| Public exploit moduleA module existing is not the same as active exploitation. | None known | Metasploit |
| EUVD cross-referenceENISA's record: CVSS 8.6 (v3.1), assigned by adobe. | Listed | ENISA EUVD |
Description
NVDAcrobat 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.
What CISA says to do
