Malicious PDF — malware analysis report

Static analysis result for SHA-256 0cb947c9dd205926…

MALICIOUS

PDF

37.4 KB Created: 2021-06-22 18:11:50 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 4088200d0891bc53a9480e8784da168a SHA-1: 017bcfdebf12411c6afccc2702d7918e78c15c5e SHA-256: 0cb947c9dd2059263482ccd25775c6be4152230ce3de9b7f0de230d32b0252d5
220 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains multiple links to malicious redirectors and a link farm, masquerading as game hacks and free item generators. The primary lure is for Roblox and Coin Master, aiming to trick users into clicking through to potentially harmful sites. The document's structure and embedded links strongly suggest a phishing or scam campaign designed to drive traffic to malicious infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • 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.
  • 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
  • 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/roblox-hack-august-2021-game-hack In PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/expensive-avatar-for-free-roblox_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/app-for-free-spins-on-coin-master_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/clip60-upload-avxiy74olhs-get-free-pants-roblox-2021_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/how-to-hack-roblox-accounts-2021_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spin-ml_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/easy-way-to-get-free-robux-on-ipad_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-link-no-verification_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/is-coin-master-hack-safe_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-promo-codes-for-roblox-items-2021_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/minecraft-mac-free_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/minecraft-pe-free-apk_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-coins-and-spins-for-coin-master_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/minecraft-free-school_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/hack-coin-master-game_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/is-free-robux-real_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/play-coin-master-online-free_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/how-to-hack-roblox-for-free-robux-by-playing-games_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/tower-of-hell-roblox-hack_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-roblox-adopt-me-accounts_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-roebucks_GM431946152.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
stream_002_off000036e8.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x36E8 23620 bytes
SHA-256: ec8372f47e331fa1fa06d3bf7d70ee24585a32f0298024d1434878c662c6e779
font_01_sfnt_off00006c3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6C3F 19300 bytes
SHA-256: 3502113527c5f7daea0f1c4271d551d520e99ef41b3bde9e08f055ab34fcc109