Malicious PDF — malware analysis report

Static analysis result for SHA-256 757d7ed9646dfd8d…

MALICIOUS

PDF

44.3 KB Created: 2021-06-06 23:27:29 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: 483b2e641ecb164c4ec6aba06287fe70 SHA-1: 72eef9d3f927c20965c1069710b2258048eae759 SHA-256: 757d7ed9646dfd8ddf8e9dfdf1374773337340f268d01336b1e811c0ca108bba
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are structured as SEO link farms and offer game cheats or free in-game currency. The ML classifier strongly indicated maliciousness, and the presence of embedded URLs and a download button lure suggests a phishing or malware distribution attempt. No scripts were extracted, but the overall structure points to a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9865

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.tw/app/431946152/paint-hack-roblox-game-hack
    • https://www.vadai.sg/uploaded_files/userfiles/files/daily-free-spin-link-in-coin-master_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/how-to-get-minecraft-for-free-on-ps4_GM479516143.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/free-coins-coin-master-link_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/how-to-robux_GM431946152.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/how-to-get-a-refund-on-roblox-2021_GM431946152.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/how-do-you-hack-minecraft_GM479516143.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/today-free-spin-coin-master_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/coin-master-hack-mod-apk-35-8_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/free-texture-packs-for-minecraft-pe_GM479516143.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/get-free-spins-for-coin-master_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/how-to-get-free-robux-generator_GM431946152.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/regal-world-coin-master_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/minecraft-bedrock-hacks-windows-10_GM479516143.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/earn-robux-sites_GM431946152.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/wurst-hacks_GM479516143.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/free-roblox-hack-us_GM431946152.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/robuxlove-net-free-robux_GM431946152.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/how-to-get-free-spins-on-coin-master-iphone_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/coin-master-free-coins_GM406889139.pdf
    • https://www.vadai.sg/uploaded_files/userfiles/files/minecraft-build-hacks_GM479516143.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off000051a6.bin
ec87609fc533cdcdab89e8faff2b72c630a80b0bf0deaa05fb0d20272fd90889
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x51A6 25424 bytes
font_01_sfnt_off000089b1.bin
44dadef92978b5a85b566e86d42080b448457ad6f9f708909e41ab483cf4b6d1
pdf-font-stream PDF embedded font (sfnt) at offset 0x89B1 18560 bytes