Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9c75a9eaf5fe4c3…

MALICIOUS

PDF

48.5 KB Created: 2021-06-03 13:19:03 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 73ad598bed086567568a213ea2538400 SHA-1: 42399973d73c2cab85d4bcc1261c23e38099f56e SHA-256: b9c75a9eaf5fe4c344c0d62b275efd474f75218b83780dcc41fcf115b1605ee0
260 Risk Score

Malware Insights

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

The PDF file contains multiple heuristics indicating malicious intent, including a lure for game hacks and impersonation of Amazon. It directs users to a malicious URL that is associated with redirector infrastructure. The presence of a fake CAPTCHA and download button further supports a phishing or scam attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9796

Heuristics 7

  • 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.
  • Fake CAPTCHA / human verification prompt high SE_FAKE_CAPTCHA
    Document displays a fake CAPTCHA or human-verification prompt — used to trick users into running commands or pressing keyboard shortcuts
  • Brand-impersonation credential phishing lure high SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: call-to-action link host does not match the impersonated brand: https://netcdn.online/app/431946152/how-to-get-free-robux-on-tablet-easy-game-hack.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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.online/app/431946152/how-to-get-free-robux-on-tablet-easy-game-hack In PDF document text
    • http://libnh.stikesnh.ac.id/repository/roblox-free-robux-hack_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/how-to-get-spins-on-coin-master-hack_GM406889139.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/coin-master-cheat-to-get-free-spins_GM406889139.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-coins-and-spins-for-coin-master_GM406889139.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-robux-no-human-verification-or-survey-2021_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/roblox-free-robux-google-chrome_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-robux-com-real_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/rbx-free-robux_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/coin-master-free-spins-link-2021_GM406889139.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/how-to-get-free-robux-on-iphone_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/minecraft-tools_GM479516143.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/rblx-gg-free-robux_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/minecraft-education-edition-free_GM479516143.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-robux-promo-codes-2021_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-robux-redeem-codes_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/coin-master-games-download-free_GM406889139.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/coin-master-free-link-facebook_GM406889139.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-roblox-followers-generator_GM431946152.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-coin-spin-coin-master_GM406889139.pdfIn PDF document text
    • http://libnh.stikesnh.ac.id/repository/free-roblox-cards-pin-number_GM431946152.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
stream_004_off0000542f.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x542F 25572 bytes
SHA-256: 588bcfd2dd69e266b6a10366d52b9d9cfa8988a27c3fa15a2d462087b63d90a9
font_01_sfnt_off00008f79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8F79 2820 bytes
SHA-256: e5f6ec650849eefe6bc6a1649c2875ce35328d23e4196945bba66cc43e5a49d4
font_02_sfnt_off00009918.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9918 18764 bytes
SHA-256: 997c37247ba5df050d8c19b2711fc2a1855feede60e0200e59d9da4c81a308a0