Malicious PDF — malware analysis report

Static analysis result for SHA-256 65ffbb561ea8bfbd…

MALICIOUS

PDF

45.7 KB Created: 2021-05-18 05:07:27 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: ca2268fc80a7135e3b0060e2f9060058 SHA-1: 70259da36d0db541eea22682a140e0aada9d71a7 SHA-256: 65ffbb561ea8bfbdcccd2c031a7db78b5f284ce37a22b9f632b636185b0d6208
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File

The PDF document contains numerous links to external websites, many of which are SEO-optimized PDFs designed to appear as hack tools or generators for games like Coin Master and Roblox. The ML classifier strongly indicated maliciousness, and the presence of a "download button" heuristic further supports a lure-based attack. The primary goal appears to be directing users to download potentially unwanted or malicious applications from the linked URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9432

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • External URI info PDF_URI
    PDF contains an external URL action
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://netcdn.xyz/app/406889139/coin-master-hack-tool-apk-download-game-hack
    • https://foc.vn/public/upload/files/coin-master-hack-cheat-generator-coins-and-spins-unlimited_GM406889139.pdf
    • https://foc.vn/public/upload/files/is-there-a-way-to-get-free-robux_GM431946152.pdf
    • https://foc.vn/public/upload/files/coin-master-card-collection-link_GM406889139.pdf
    • https://foc.vn/public/upload/files/hacks-to-get-free-robux_GM431946152.pdf
    • https://foc.vn/public/upload/files/online-coin-master-free-spin-app_GM406889139.pdf
    • https://foc.vn/public/upload/files/robux-hack-tools_GM431946152.pdf
    • https://foc.vn/public/upload/files/where-to-get-free-robux_GM431946152.pdf
    • https://foc.vn/public/upload/files/completed-coin-master-hack_GM406889139.pdf
    • https://foc.vn/public/upload/files/free-spins-coin-master-2021-no-verification_GM406889139.pdf
    • https://foc.vn/public/upload/files/coin-master-hack-safe_GM406889139.pdf
    • https://foc.vn/public/upload/files/optifine-mcpe_GM479516143.pdf
    • https://foc.vn/public/upload/files/minecraft-bedrock-hacks-windows-10_GM479516143.pdf
    • https://foc.vn/public/upload/files/coin-master-free-spins-hack_GM406889139.pdf
    • https://foc.vn/public/upload/files/how-to-hack-a-roblox-account-2021_GM431946152.pdf
    • https://foc.vn/public/upload/files/coin-master-hack-tool-pc_GM406889139.pdf
    • https://foc.vn/public/upload/files/how-to-get-free-robux-on-mobile_GM431946152.pdf
    • https://foc.vn/public/upload/files/wurst-hacks_GM479516143.pdf
    • https://foc.vn/public/upload/files/free-robux-now_GM431946152.pdf
    • https://foc.vn/public/upload/files/free-robux-no-human-verification-or-survey-or-download-2021_GM431946152.pdf
    • https://foc.vn/public/upload/files/minecraft-free-download-ios_GM479516143.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00004b0f.bin
a592b42b1b127d77493020f29068733884c116ff8e2a43e47deb96e6eddda07e
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4B0F 24236 bytes
font_01_sfnt_off00008212.bin
dbaa9c12d07f3632734605f1d5d6dee3ad5af1f57488e46d95dab68b383f08c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x8212 4020 bytes
font_02_sfnt_off00008f9a.bin
ab3dfcf4bb97e5e0fbede254535527088a6d4b49c17ed7a7055a18d15f385141
pdf-font-stream PDF embedded font (sfnt) at offset 0x8F9A 18472 bytes