CVE-2026-34621
Adobe Acrobat and Reader: Prototype Pollution
As of , CVE-2026-34621 in Adobe Acrobat and Reader is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch soon.
- Exploited
- Yes: CISA listed it on 13 April 2026
- US federal deadline
- 27 April 202614 days after CISA listed it. US federal civilian agencies must fix it by then.
- Used in ransomware campaigns
- Not known to CISA
- EPSS score
- 0.02Higher than 81% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
- Public exploit
- None foundNeither Metasploit nor Exploit-DB lists one.
- Fix
- Vendor advice: helpx.adobe.comLinks below, from CISA's entry.
What CISA says to do
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's required action
What the flaw is
Adobe Acrobat and Reader contain a prototype pollution vulnerability that allows for arbitrary code execution.
CISA's 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.
The CVE record's description, from adobe
- CVE published
- 11 April 2026
- Assigned by
- adobe
- CVSS
- 8.6 High (CVSS 3.1, from the CNA)
- CWE-1321
- Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')
- CISA SSVC, exploitation
- active
- CISA SSVC, automatable
- no
- CISA SSVC, technical impact
- total
Timeline
- The CVE record was published.
- CISA added it to its list of exploited vulnerabilities.
- The US federal deadline to fix it.
Acrobat and Reader: other exploited entries
| Vulnerability | Product | Our group | Listed | Deadline | EPSS |
|---|---|---|---|---|---|
| CVE-2009-3459Heap-Based Buffer Overflow | Adobe Acrobat and Reader | Patch this weekMetasploit module; EPSS 0.87; verified Exploit-DB entry | 0.87 | ||
| CVE-2007-5659Buffer Overflow | Adobe Acrobat and Reader | Patch this weekMetasploit module; EPSS 0.87; verified Exploit-DB entry | 0.87 | ||
| CVE-2009-3953Universal 3D Remote Code Execution | Adobe Acrobat and Reader | Patch this weekMetasploit module; EPSS 0.83; verified Exploit-DB entry | 0.83 | ||
| CVE-2009-4324Use-After-Free | Adobe Acrobat and Reader | Patch this weekMetasploit module; EPSS 0.82; verified Exploit-DB entry | 0.82 | ||
| CVE-2010-2883Stack-Based Buffer Overflow | Adobe Acrobat and Reader | Patch this weekMetasploit module; EPSS 0.81; verified Exploit-DB entry | 0.81 | ||
| CVE-2008-2992Reader and Acrobat Input Validation | Adobe Acrobat and Reader | Patch this weekRansomware use; Metasploit module; EPSS 0.98; verified Exploit-DB entry | 0.98 | ||
| CVE-2023-21608Use-After-Free | Adobe Acrobat and Reader | Patch this weekEPSS 0.61 | 0.61 | ||
| CVE-2021-21017Heap-based Buffer Overflow | Adobe Acrobat and Reader | Patch this weekEPSS 0.86 | 0.86 | ||
| CVE-2021-28550Use-After-Free | Adobe Acrobat and Reader | Patch this weekEPSS 0.52 | 0.52 | ||
| CVE-2008-0655Unspecified | Adobe Acrobat and Reader | Patch soon | 0.38 |
Read further
- CVE recordcve.org
- NVD entrynvd.nist.gov
- CISA's catalogcisa.gov
- EPSS for this CVEapi.first.org