CVE-2021-40719Network attack vector

Unauthenticated code execution via unsafe AMF deserialization

Published Oct 21, 2021 · Updated Apr 23, 2025

Deserialization of untrusted data in Adobe Connect 11.2.3 and earlier allows remote attackers to execute arbitrary code through AMF messages. The server deserializes attacker-supplied Action Message Format messages in a way that enables arbitrary method invocation. No authentication or user interaction is required, and successful invocation runs code in the server's security context.

CVSS severity9.8
Critical
EPSS probability3.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization of untrusted data in Adobe Connect 11.2.3 and earlier allows remote attackers to execute arbitrary code through AMF messages. The server deserializes attacker-supplied Action Message Format messages in a way that enables arbitrary method invocation. No authentication or user interaction is required, and successful invocation runs code in the server's security context.

The record

CVE
CVE-2021-40719
Published
Oct 21, 2021
Updated
Apr 23, 2025
Vendor
Adobe
Product
Adobe Connect
Classifications
CWE-502, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 21, 2021CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record 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=unspecified <=11.2.3
  2. Affected versionversion=unspecified <=None

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Adobe · Adobe Connectversion=unspecified <=11.2.3; version=unspecified <=None

Published CVSS scores

9.8AdobeCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 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
T1190Exploit Public-Facing Application

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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