Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9b7e3471296f927…

MALICIOUS

PDF

35.4 KB Created: 2021-06-28 12:29:38 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-13
MD5: cd2f9c4b2e7c99f73862ac00afcabc53 SHA-1: 50324eb3fe5b4e90daa1ac2101ebe94ae30f08cf SHA-256: b9b7e3471296f927aae72f6ee9553179dfcc964e3d8aa70332dcd679ab7af5f5
220 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are part of a link farm designed to lure users with promises of free in-game currency or hacks for popular games like Roblox and Coin Master. One primary URL, http://netcdn.co/app/431946152/can-you-make-a-roblox-game-for-free-game-hack, is identified as a malicious redirector. The document body and embedded links strongly suggest a phishing or scam attempt to drive traffic to potentially malicious sites.

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/can-you-make-a-roblox-game-for-free-game-hack In PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/free-robux-hack-2021_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/how-to-hack-roblox-for-robux_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/roblox-accounts-for-sale-free_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/coin-master-free-in-app-purchases_GM406889139.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/300-free-spins-coin-master_GM406889139.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/click-to-claim-free-robux_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/free-download-coin-master_GM406889139.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/free-robux-without-downloading-apps-on-ipad_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/free-robux-gift-card-codes_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/how-to-hack-roblox_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/how-to-make-your-own-minecraft-pe-server-for-free_GM479516143.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/easy-ways-to-get-free-robux_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/minecraft-realms-free_GM479516143.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/coin-master-heaven-free-daily-spins_GM406889139.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/coin-master-gold-cards-hack_GM406889139.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/how-to-make-roblox-clothes-for-free_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/www-free-robux_GM431946152.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/free-spin-link-coin-master_GM406889139.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/coin-master-mod-version-free-download-v344_GM406889139.pdfIn PDF document text
    • https://www.opertus-me.com/uploaded_files/userfiles/files/nathorix-hacker-free-robux_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
font_00_sfnt_off00003124.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3124 22816 bytes
SHA-256: b3ff33dcf7e435564cb0faab36f849b34e1ba2fa532da05909561c3c753f1282
font_01_sfnt_off0000640d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x640D 19576 bytes
SHA-256: ccb2dad24eb6fdc7da62a8cb85c4a0a2a10e9d29b174362bdc9658defcdd91ba