Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf99456b0776cc4b…

MALICIOUS

PDF

37.9 KB Created: 2021-07-25 07:48:07 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-27
MD5: fafc962d33dacc01b9a83ebb4c0d0668 SHA-1: b9c9614f9940fc21b19c2d061df83c5f4433d7ce SHA-256: cf99456b0776cc4b03192e4fc57353eca9971709593b5064921da43b9b1d5eb1
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains links to malicious redirectors disguised as game hacks and generators, aiming to trick users into downloading further malware. The embedded URLs, such as http://netcdn.tw/app/479516143/minecraft-java-edition-download-free-game-hack, are indicative of a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest a malicious redirector workflow, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9529

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/479516143/minecraft-java-edition-download-free-game-hack In PDF document text
    • https://kierowcyhgv.uk/images/download-minecraft-free-hiapphere_GM479516143.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/minecraft-pe-free-download-ios-no-jailbreak_GM479516143.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/will-minecraft-dungeons-be-free_GM479516143.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/how-to-hack-robux_GM431946152.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/how-to-get-hacks-on-minecraft_GM479516143.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/how-to-get-free-coins-on-coin-master_GM406889139.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/coin-master-free-spins-link-today-new-2021_GM406889139.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/free-robux-roblox-promo-codes_GM431946152.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/minecraft-free-download-windows-10_GM479516143.pdfIn PDF document text
    • https://kierowcyhgv.uk/images/how-to-get-minecraft-for-free-on-ipad_GM479516143.pdfIn PDF document text
    • http://en.wikipedia.org/wiki/MIT_LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000033e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x33E1 22816 bytes
SHA-256: 5bf2b4209dbefabf39961761166eeb201f9450faafe3585c2008000abc35f70e
font_01_sfnt_off00006712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6712 2940 bytes
SHA-256: eb230542719c96b42e3fd8bb01e35f13ebd5f02629049da3a58e7fd7607bf48a
font_02_sfnt_off00007122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7122 18572 bytes
SHA-256: b44bcce2d8515c0d099a66814c088ed689798a3dbc3c1364cf14b7c888151b67