CVE-2026-34659Network attack vector

User-context code execution via unsafe deserialization

Published May 12, 2026 · Updated May 12, 2026

Deserialization in Adobe Connect Desktop Application 2025.9.15, 2025.8.157 and earlier allows remote attackers to execute code. The application processes attacker-controlled serialized data reached through a crafted URL or compromised web page, but Adobe has not disclosed the parser, data format, or code locus. A victim must visit the URL or interact with the page, after which code runs in the victim's user context on the Windows or macOS host.

CVSS severity9.6
Critical
EPSS probability0.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization in Adobe Connect Desktop Application 2025.9.15, 2025.8.157 and earlier allows remote attackers to execute code. The application processes attacker-controlled serialized data reached through a crafted URL or compromised web page, but Adobe has not disclosed the parser, data format, or code locus. A victim must visit the URL or interact with the page, after which code runs in the victim's user context on the Windows or macOS host.

The record

CVE
CVE-2026-34659
Published
May 12, 2026
Updated
May 12, 2026
Vendor
Adobe
Product
Adobe Connect
Classifications
CWE-502, CAPEC-586, T1204.001, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 12, 2026CVE publishedPublication date reported by the CVE source.
  2. May 12, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2025.8.157

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Adobe · Adobe Connectversion=0 <=2025.8.157

Published CVSS scores

9.6AdobeCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
CAPEC-586Object Injection
T1204.001Malicious Link
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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