Malicious PDF — malware analysis report

Static analysis result for SHA-256 db4860c26a18d80b…

MALICIOUS

PDF

49.1 KB Created: 2021-05-13 03:47:35 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-01
MD5: c757158b3a5e9b572ee6783874d93588 SHA-1: 961b6a6c91f7438b8eb4e79053faddff382d0802 SHA-256: db4860c26a18d80b909f291574a51c39ee73496d279acd416509889245702054
142 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, routes users through malicious redirector infrastructure and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8642

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.
  • PDF links to a 'free generator / game hack' redirector high PDF_GAME_HACK_REDIRECT_LURE
    PDF's clickable action targets a redirector of the form /app/<id>/<slug>-game-hack — the landing-page shape of a large SEO 'free spins / generator / game hack' lure family that funnels victims through rotating disposable hosts to a malware/scam payload. The multi-link variants also trip ML/link-farm rules; this catches the single-link variants that otherwise score clean.
  • 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/free-robux-offers-game-hack PDF link annotation
    • https://zapoj-kharkov.com.ua/images/coin-master-32-android-mod-hack-apk-download_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/is-roblox-free-on-nintendo-switch_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/websites-that-give-you-free-robux_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/moonactive-coin-master-hack_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/how-to-get-free-robux-2021_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/coin-master-free-spins-link-2021-hack_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/coin-master-pc-hack-download_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/free-robux-without-downloading-apps_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/free-spins-for-coin-master-app_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/free-robux-human-verification_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/roblox-play-now-for-free_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/coin-master-daily-free-spins-link-today-facebook_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/coin-master-free-spins-without-human-verification_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/free-minecraft-for-kids_GM479516143.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/how-to-get-minecraft-for-free_GM479516143.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/free-robux-scam_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/coin-master-ids-for-free-spins_GM406889139.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/roblox-free-download_GM431946152.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/minecraft-windows-10-edition-free-with-java_GM479516143.pdfIn PDF document text
    • https://zapoj-kharkov.com.ua/images/free-coins-and-spins-coin-master-2021_GM406889139.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00004a65.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4A65 25348 bytes
SHA-256: 60d3def37eb9510a847fde3e1a1dfd715bda16e13902959879ee905b939ec9e0
font_01_sfnt_off00008472.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8472 2824 bytes
SHA-256: 94c1b019735d7e491765340abe50b2897410e2ec65ecf141c08bd9f2220897c4
font_02_sfnt_off00008e1c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8E1C 6636 bytes
SHA-256: 62075f0fe13502d46afb6e55e83d440c29ef4988399537df1f86e7653ce3b744
font_03_sfnt_off00009e28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9E28 18012 bytes
SHA-256: 2fb616bca13af88ff89276a9b2d2fcc075dc4ebb9507e4cf45ab0719cef726f6