Malicious PDF — malware analysis report

Static analysis result for SHA-256 7644fca851ca0bdf…

MALICIOUS

PDF

43.7 KB Created: 2021-05-14 01:01:48 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: a006cfc0e30664737e44ee1598a76ae6 SHA-1: 043797ece145ca360264a3a902d29adcf8982ccd SHA-256: 7644fca851ca0bdf96c7eff54c9f0911a6eca01937253805cd4a6a239e925d2b
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains numerous links to external websites, likely part of a link farm designed to attract traffic. It also presents a fake CAPTCHA or human verification prompt, a common social engineering tactic to trick users into interacting with malicious content. The ML classifier strongly flagged this PDF as malicious, indicating a high probability of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 5

  • 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.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • 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/431946152/roblox-group-free-robux-game-hack
    • https://www.sg-escholzmatt.ch/images/earn-free-robux-on-roblox_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/minecraft-hacks-list_GM479516143.pdf
    • https://www.sg-escholzmatt.ch/images/can-you-get-minecraft-for-free_GM479516143.pdf
    • https://www.sg-escholzmatt.ch/images/freespincoin-masterlinkdownload_GM406889139.pdf
    • https://www.sg-escholzmatt.ch/images/free-roblox-hair-boy_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/coin-master-free-spin-daily-bonus_GM406889139.pdf
    • https://www.sg-escholzmatt.ch/images/coin-master-hack-without-root_GM406889139.pdf
    • https://www.sg-escholzmatt.ch/images/coin-master-hack-to-get-free-spins_GM406889139.pdf
    • https://www.sg-escholzmatt.ch/images/coin-master-fan-page-free-spins_GM406889139.pdf
    • https://www.sg-escholzmatt.ch/images/how-to-change-username-on-roblox-for-free_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/bloxland-earn-free-robux_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/minecraft-hacks-xbox_GM479516143.pdf
    • https://www.sg-escholzmatt.ch/images/free-roblox-toy-codes-not-used_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/bit-ly-coin-master-hack_GM406889139.pdf
    • https://www.sg-escholzmatt.ch/images/free-roblox-adopt-me-accounts_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/free-account-roblox-2021_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/how-to-get-free-robux-without-verifying-2021_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/how-do-you-get-free-robux_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/roblox-free-robux-no-human-verification_GM431946152.pdf
    • https://www.sg-escholzmatt.ch/images/coin-master-free-spins-youthnow_GM406889139.pdf
    • https://robuxhaxs.com
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off000049bb.bin
8d2b57d175c528a2b4ae4ffccf4433588a7fff07d0082d63b64db3d248854fb0
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x49BB 27340 bytes
font_01_sfnt_off000088bc.bin
b2792b9995997ff68e5dfa2acea2bbc639d657441038e216f117c3302624ca62
pdf-font-stream PDF embedded font (sfnt) at offset 0x88BC 18264 bytes