Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b4f3f1584215a53…

MALICIOUS

PDF

35.1 KB Created: 2021-06-22 21:25:00 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-31
MD5: a5a17ef902623dfcf454917434835ba0 SHA-1: 4f9120f1fc316ae50e74828412db1f8014197569 SHA-256: 4b4f3f1584215a53eace486e1017b3236a0e219c44c78e5a37ee2cf1782f910e
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains multiple links, including one pointing to known malicious redirector infrastructure. The document body explicitly mentions 'How To Get Free Unlimited Robux On Roblox 2021' and 'game hack', indicating a lure for potentially unwanted or malicious content. The presence of a malicious redirector suggests the intent is to lead the user to a site that may host further malware or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 4

  • PDF links to a 'free generator / game hack' redirector critical 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. CRITICAL on its own: the /app/<id>/<slug>-game-hack path shape is unambiguous scam infra, and the host rotates so a host-list match can't be relied on.
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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
  • 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 http://netcdn.co/app/431946152/how-to-get-free-unlimited-robux-on-roblox-2021-game-hack In PDF document text
    • http://achauco.vn/public/upload/files/earn-free-spins-coin-master_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/coin-master-hack-mod-apk-2021_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/is-it-possible-to-get-free-robux_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/free-roblox-accounts-with-robux_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/free-game-packs-for-coin-master_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/coin-master-free-shield_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-free-hair-girl_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-free-robux-generator_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-promo-codes-free-robux_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-login-play-online-for-free_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/no-scam-free-robux_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/how-to-get-free-coins-in-coin-master-game_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-gucci-shirt-free_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/robux-for-kids_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/minecraft-education-free_GM479516143.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/free-roblox-clothes-boy_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/coin-master-free-cards-link_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-jailbreak-hack_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/minecraft-games-free-download_GM479516143.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/will-minecraft-ever-be-free_GM479516143.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00002ebd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2EBD 22668 bytes
SHA-256: 32e5b2b51cb5fb6f99e3e846a9f2ac01cad3b0b5d38906234ebca8c9c695a038
font_01_sfnt_off00006138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6138 20012 bytes
SHA-256: 6550ba4c9d8a3428ad66ed6784cf44b2f132c4285ebc73daca288e06cfc8acb6