Malicious PDF — malware analysis report

Static analysis result for SHA-256 2131cccbd1238a2a…

MALICIOUS

PDF

34.4 KB Created: 2021-07-19 21:04:06 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 37c36744f2ef7a8c6a1fa1dee73acff5 SHA-1: 0d0193f53461a429ba0a1e8d83c8d9b69272e6aa SHA-256: 2131cccbd1238a2a4371b2a4b20eb70fbd165cef4bf45814bed54c8c6fb625d3
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document employs a lure for game-related cheats and free currency, directing users to a known malicious redirector. The embedded link, http://netcdn.tw/app/406889139/coin-master-free-coins-and-spins-app-game-hack, is designed to exploit user interest and likely leads to further malicious content or downloads. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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.tw/app/406889139/coin-master-free-coins-and-spins-app-game-hack In PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/free-coin-master-spins_GM406889139.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/how-to-get-minecraft-for-free-ios_GM479516143.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/free-minecraft-account_GM479516143.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/minecraft-free-download-pc_GM479516143.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/coin-master-hacks_GM406889139.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/coin-master-free-spin-codes_GM406889139.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/minecraft-pe-free-apk_GM479516143.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/free-coin-master-spins-link_GM406889139.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/earn-free-robux-on-roblox_GM431946152.pdfIn PDF document text
    • https://www.alloywheels.in/uploaded_files/userfiles/files/rblx-gg-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
stream_002_off00002ec5.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x2EC5 24044 bytes
SHA-256: fb7330ff0e931c87737b4696647fe21938ff2436c88b2b80e92fa4d4f67ba68c
font_01_sfnt_off0000655e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x655E 18060 bytes
SHA-256: f77ee24e01944806ea28e16fd73427a54f7109e241804df06ce657d8c6d11cfb