CVE-2026-21318 – CVE-2026-21318 is an out-of-bounds write vulner... (How to Fix)

Q: What is the severity of CVE-2026-21318?

CVE-2026-21318 has a CVSS score of 7.8 (HIGH). CVE-2026-21318 is an out-of-bounds write vulnerability in Adobe After Effects that could allow arbitrary code execution when a user opens a malicious file. This affects After Effects 25.6 and earlier versions, putting users who open untrusted project files at risk.

📋 TL;DR

CVE-2026-21318 is an out-of-bounds write vulnerability in Adobe After Effects that could allow arbitrary code execution when a user opens a malicious file. This affects After Effects 25.6 and earlier versions, putting users who open untrusted project files at risk.

💻 Affected Systems

Products:

Adobe After Effects

Versions: 25.6 and earlier

Operating Systems: Windows, macOS

Default Config Vulnerable: ⚠️ Yes

Notes: All default installations of affected versions are vulnerable. No special configuration required for exploitation.

📦 What is this software?

After Effects by Adobe

View all CVEs affecting After Effects →

⚠️ Risk & Real-World Impact

🔴

Worst Case

Full system compromise with attacker gaining the same privileges as the current user, potentially leading to data theft, ransomware deployment, or persistent backdoor installation.

🟠

Likely Case

Malware installation or data exfiltration through social engineering attacks where users open malicious After Effects project files.

🟢

If Mitigated

Limited impact if users only open trusted files from verified sources and have proper endpoint protection.

🌐 Internet-Facing: LOW - Exploitation requires user interaction with malicious files, not network exposure.

🏢 Internal Only: MEDIUM - Internal users could be targeted via phishing with malicious project files.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Exploitation requires user interaction (opening malicious file) and knowledge of file format manipulation.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: 25.7 or later

Vendor Advisory: https://helpx.adobe.com/security/products/after_effects/apsb26-15.html

Restart Required: Yes

Instructions:

1. Open Adobe Creative Cloud application. 2. Navigate to 'Apps' section. 3. Find After Effects and click 'Update'. 4. Wait for download and installation. 5. Restart After Effects when prompted.

🔧 Temporary Workarounds

Restrict file opening

all

Configure system policies to prevent opening of untrusted .aep files

Sandbox execution

all

Run After Effects in isolated environment or virtual machine

🧯 If You Can't Patch

Implement application whitelisting to prevent execution of malicious payloads
Train users to never open After Effects files from untrusted sources

🔍 How to Verify

Check if Vulnerable:

Check After Effects version via Help > About After Effects. If version is 25.6 or earlier, system is vulnerable.

Check Version:

On Windows: Check version in Help > About. On macOS: After Effects > About After Effects

Verify Fix Applied:

Verify After Effects version is 25.7 or later after update.

📡 Detection & Monitoring

Log Indicators:

Unexpected crashes of After Effects
Unusual file access patterns from After Effects process

Network Indicators:

Outbound connections from After Effects to unknown IPs after file opening

SIEM Query:

Process:After Effects AND (EventID:1000 OR ParentProcess:explorer.exe) AND FileExtension:.aep

📊 Metadata

CVE ID: CVE-2026-21318

CVSS v3 Score: 7.8 (HIGH)

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

CWE: CWE-787

EPSS Score: 0.01% exploit probability (0.6th percentile)

Published: February 10, 2026

Last Updated: February 11, 2026

🔗 References

https://helpx.adobe.com/security/products/after_effects/apsb26-15.html Vendor Advisory

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2026-21318, you might also want to check these: