CVE-2026-34621: Adobe Acrobat and Reader Prototype Pollution Vulnerability
Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.
Generated by VEDAS. Scores as of 2026-11-01 19:19 UTC. Rebuilt every few hours from cve-scores, CISA KEV and vedas-signatures. How this works and its limits.
What it is
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.
Description quoted from the CVE record (assigned by adobe, published 2026-04-11).
Weakness: Improperly Controlled Modification of Object Prototype Attributes (‘Prototype Pollution’) (CWE-1321)
How it can be exploited
Exploitable with local access with low attack complexity needing no privileges and a user must take an action. Impact: confidentiality high, integrity high, availability high. CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
CISA assessment (SSVC): CISA assesses exploitation as active. Automatable: no. Technical impact: total.
- On CISA KEV since
- 2026-04-13
- US federal deadline
- 2026-04-27
- Ransomware use
- Not known
Public exploit evidence (Exploit Observer)
Also known as: BDU:2026-04929, EUVD-2026-21675, GHSA-vcqh-932g-m3qj
Exploit Observer links 6 pieces of public exploit code or detection modules that name this CVE or one of its aliases.
Exploit code and modules (6)
Code that names this CVE. A repository can be a working exploit, a scanner, a fake or malware; read it before running anything.
- Code repository: https://github.com/azefzafyoussef/cve-2026-34621
- Code repository: https://github.com/eduardorossi84/cve-2026-34621-poc
- Code repository: https://github.com/ercihan/cve-2026-34621
- Code repository: https://github.com/ercihan/cve-2026-34621_pdf_sample
- Code repository: https://github.com/keulenr01/remediate-adobeacrobat-cve-2026-34621
- Code repository: https://github.com/null200ok/cve_2026_34621_advanced
Vulnerability databases and vendor advisories (5)
Catalogue entries, not exploit evidence.
- Vulnerability database or vendor advisory: https://euvd.enisa.europa.eu/enisa/EUVD-2026-21675
- Vulnerability database or vendor advisory: https://github.com/advisories/GHSA-vcqh-932g-m3qj
- Vulnerability database or vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-34621
- Vulnerability database or vendor advisory: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34621
- Vulnerability database or vendor advisory: https://www.tenable.com/cve/CVE-2026-34621
10 more references returned by Exploit Observer did not name this CVE or an alias, so they are left out.
VEDAS data as of 2026-11-01T17:12 UTC; fetched 2026-11-02.
Live scores
- EPSS
- 0.072
some chance of attack soon - VEDAS
- 0.756
some exploit evidence - On CISA KEV
- Yes, since 2026-04-13
- Detection rule
- Out of scope (local)
Thin horizontal line: the “likely” (EPSS 0.10) or “strong” (VEDAS 0.90) threshold. Shaded “no data” areas are periods when cve-scores did not publish.
Who is affected
| Product | Affected | Not affected |
|---|---|---|
| Adobe Acrobat DC | up to and including 26.001.21367 | 26.001.21411 is not affected |
| Adobe Acrobat Reader DC | up to and including 26.001.21367 | 26.001.21411 is not affected |
| Adobe Acrobat 2024 | up to and including 24.001.30356 | 24.001.30362 (Win), 24.001.30360 (Mac) is not affected |
Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.
Exploit Observer also maps it to: adobe acrobat, adobe acrobat_dc, adobe acrobat_reader_dc, adobe_systems_inc. adobe_acrobat_2024, adobe_systems_inc. adobe_acrobat_document_cloud, adobe_systems_inc. adobe_acrobat_reader_document_cloud.
How to fix it
CISA 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.
Vendor guidance:
- https://helpx.adobe.com/security/products/acrobat/apsb26-43.html (vendor-advisory)
How to detect it
This bug needs local access to exploit. VEDAS signatures cover remotely exploitable bugs for now, so there is no network rule or remote check for it. Patch it and watch your endpoint telemetry for unusual local activity.
References
Vendor advisories and patches
- https://helpx.adobe.com/security/products/acrobat/apsb26-43.html (vendor-advisory)
Government sources
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-34621 (government-resource)
Other databases
Where this comes from
This advisory is generated automatically by VEDAS from: CVE.org record, CISA KEV, cve-scores (EPSS and VEDAS), Exploit Observer. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.