Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b81a09856fd60a2…

MALICIOUS

PDF

250.6 KB Created: 2021-07-05 05:53:18 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-10-26
MD5: a47b00e6a24836282625efc0cba3ea9e SHA-1: 9e21fd62febfc1613c9b8e8c8427b2f4ae0f9622 SHA-256: 8b81a09856fd60a27b2c1ffc0ead35c30c8da772737e8fc33f63ee037dc0099a
258 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1539 Steal or Modify Data

The PDF file contains multiple heuristics indicating a credential phishing and redirection lure. It presents a fake CAPTCHA and impersonates the brand 'Apple' to trick users into clicking a link. This link, http://netcdn.tw/app/1330123889/pubg-5-uc-buy-game-hack, leads to a malicious redirector, likely intended to harvest credentials or abuse MFA. The document's content and structure strongly suggest an attempt to deceive the user into performing an action that compromises their account security.

Machine Learning

  • Nyx PDF Classifier clean score 0.0098

Heuristics 8

  • 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
  • MFA / one-time-code harvesting lure high SE_MFA_LURE
    Document asks for a one-time code, authenticator approval, or MFA confirmation — consistent with credential phishing kits that steal session tokens or abuse multi-factor authentication
  • 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: http://netcdn.tw/app/1330123889/pubg-5-uc-buy-game-hack.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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/1330123889/pubg-5-uc-buy-game-hack In PDF document text
    • https://library.sman1berau.sch.id/repository/how-to-hack-minecraft_GM479516143.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/free-spin-link-for-coin-master_GM406889139.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/how-to-play-roblox-for-free_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/roblox-hack-edit-leaderstats_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/free-robux-no-human-verification-or-survey-2021-on-android_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/free-camp-2-on-roblox_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/get-free-robux-without-doing-anything_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/free-roblox-tickets-hack_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/how-to-get-free-robux-no-survey_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/how-to-actually-get-free-robux_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/claim-free-robux_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/coin-master-golden-cards-hack_GM406889139.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/get-me-robux_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/roblox-games-with-no-anti-cheat_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/coin-master-hack-app-android-download_GM406889139.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/how-to-get-free-robux-without-email_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/free-spins-coin-master-app_GM406889139.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/free-robux-generator-no-human-verification-fpr-real_GM431946152.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/coin-master-spin-link-today-free_GM406889139.pdfIn PDF document text
    • https://library.sman1berau.sch.id/repository/minecraft-free-ios_GM479516143.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_024_off00037da2.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x37DA2 25928 bytes
SHA-256: d9f0184d54a2d23af1ef634e22853a852e2877876df6aa29102a3684e296d47d
font_01_sfnt_off0003babb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3BABB 18440 bytes
SHA-256: 70f97ab81484be2191b69969adfd6ee3ce9b4c1cfcf3f4419a2a2923e81ccb7a