Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa3f88f2b07bf92…

MALICIOUS

PDF

43.4 KB Created: 2021-05-11 03:35:15 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2026-06-04
MD5: 8a0f62a606592eb395fd05f2ca1f7a86 SHA-1: 4f538ed54d72a3f7c64b1a57697644676c740b00 SHA-256: caa3f88f2b07bf92a3d0a15cead641d5a4cc70ac35b54ea8cced91ba4e1914fb
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier strongly indicated maliciousness, and the document body contains a lure for 'Coin Master Daily Free Spins' with embedded URLs pointing to suspicious domains. These URLs likely lead to a scam or a download of a second-stage payload, aligning with common phishing and malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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 https://netcdn.xyz/app/406889139/coin-master-daily-free-spins-link-march-2021-game-hack In PDF document text
    • http://apx-centre.ru/images/coin-master-hack-without-verification_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/free-spins-for-coin-master-ios_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/free-robux-with-no-verification-2021_GM431946152.pdfIn PDF document text
    • http://apx-centre.ru/images/haktuts-coin-master-free-daily-spins_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/how-to-get-free-robux-without-surveys_GM431946152.pdfIn PDF document text
    • http://apx-centre.ru/images/coin-master-unlimited-spin-hack-mod-apk_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/minecraft-pe-apk_GM479516143.pdfIn PDF document text
    • http://apx-centre.ru/images/free-spins-coin-master-2021_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/free-robux-no-verification-or-survey-2021_GM431946152.pdfIn PDF document text
    • http://apx-centre.ru/images/hack-coin-master-app_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/how-to-get-free-roebucks-in-roblox_GM431946152.pdfIn PDF document text
    • http://apx-centre.ru/images/coin-master-hack-no-human-verification_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/free-coin-master-coins_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/free-coin-master-link-2021_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/coin-master-free-coins--spins_GM406889139.pdfIn PDF document text
    • http://apx-centre.ru/images/free-robux-no-downloading-apps_GM431946152.pdfIn PDF document text
    • http://apx-centre.ru/images/minecraft-free-minecoins_GM479516143.pdfIn PDF document text
    • http://apx-centre.ru/images/roblox-free-robux-hack_GM431946152.pdfIn PDF document text
    • http://apx-centre.ru/images/minecraft-pe-apk-download-free-015-0_GM479516143.pdfIn PDF document text
    • http://apx-centre.ru/images/roblox-inappropriate_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_003_off00004dbe.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4DBE 24244 bytes
SHA-256: 57bfa9a236ab7c289d116574d0f5e80e71e890966eb30456eec421d8993fe153
font_01_sfnt_off000084ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x84EA 19044 bytes
SHA-256: 3f9aae1fdf8799fca0c9fecd68bec18923aee995b2022bf59fb0518bf5a4831a