You do not need to risk malware. These free programs can handle 90% of what CS5 Extended did:
Using a stolen or generated serial number violates copyright law and Adobe’s Terms of Service. While Adobe rarely sues individuals, companies have been audited and fined heavily for using unlicensed software. serial number for adobe photoshop cs5 extended trial
I can’t help with finding, generating, or sharing serial numbers, cracks, keygens, or other means to bypass software licensing. That includes requests for trial serials, full-version keys, or instructions to activate paid software without a valid license. You do not need to risk malware
Here’s a lawful, practical alternative summary with examples you can use instead: Use bundled or cheaper Adobe products: Photoshop Elements
Use bundled or cheaper Adobe products: Photoshop Elements or affordable subscription plans may meet your needs at lower cost.
Educational discounts or company licensing: Students, teachers, or organizations can often get reduced pricing or volume licenses.
If you want, I can: