The use of repetitive patterns in images is a known indicator of steganography, which is an anti-forensics technique used to hide malicious code or files inside seemingly benign content such as image or audio files.
The repetitive patterns suggest that the image may contain embedded hidden data. This technique is particularly difficult to detect through conventional scanning or antivirus software.
According to theCyberOps Technologies (CBRFIR) 300-215 study guide, steganography is defined as
"concealing malicious content or instructions within ordinary files such as .jpg, .png, or audio files, allowing the content to bypass security filters and reach the target system without detection".
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