Malicious PDF — malware analysis report

Static analysis result for SHA-256 291fa5aa35659610…

MALICIOUS

PDF

33.5 KB Created: 2021-07-20 11:50:44 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 470bf25babba270aa94584a897b88cc5 SHA-1: 7cc4c3b6e466ef86818118ed2d437365173443b2 SHA-256: 291fa5aa356596107115dfce7f294c43979d6d80bcefc5238aa583c52ff346e0
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains multiple embedded links and a call-to-action phrase, luring the user towards a 'Coin Master Free Spins App' generator. The primary link, http://netcdn.tw/app/406889139/coin-master-free-spins-app-game-hack, is identified as a malicious redirector. While no scripts were explicitly extracted, the nature of the lure and the presence of multiple PDF links suggest an attempt to drive users to malicious websites, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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-spins-app-game-hack In PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/minecraft-pe-hacks_GM479516143.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/tiktok-followers-for-free_GM835599320.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/mine-minecraft-games-for-free_GM479516143.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/free-robux-no-verification-2021_GM431946152.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/minecraft-apk-free-download_GM479516143.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/free-robux-please_GM431946152.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/roblox-hack_GM431946152.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/roblox-pink-free-robux_GM431946152.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/free-tiktok-accounts_GM835599320.pdfIn PDF document text
    • https://kejari-denpasar.go.id/public/ckfinder/userfiles/files/coin-master-hack-without-verification-2021_GM406889139.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_off00002d9c.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x2D9C 23284 bytes
SHA-256: 4a66caee7d30edbfe6f64fca2f89b23d777974f28a57ecf69117eeaf778dba7b
font_01_sfnt_off0000623b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x623B 17884 bytes
SHA-256: 21af4872a04c62c178ac31651a333ecdcea5bb1ed4ceeeef1956d42e8fc37ea8