Malicious PDF — malware analysis report

Static analysis result for SHA-256 997cf38b4d0ae87e…

MALICIOUS

PDF

33.3 KB Created: 2021-07-08 10:23:52 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-13
MD5: e469900280d6e16ab632c0eac41466a9 SHA-1: 70f15e2786477e31e0ec7f0c491ba94f77079011 SHA-256: 997cf38b4d0ae87e11683072f003f23a8e4616976697acd7475cc740b9b96463
200 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document contains multiple invisible links and visual lures designed to trick users into clicking on malicious URLs. The primary lure is for 'free Robux' and 'game hacks', leading to redirectors that host further malicious content. The ML classifier strongly indicates maliciousness, and the presence of numerous links to known malicious infrastructure supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 5

  • 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.
  • Invisible PDF links to CAPTCHA-themed web lure high PDF_CAPTCHA_LINK_LURE
    PDF contains invisible clickable link annotations that point to a CAPTCHA/capcha-themed web path. This is a common phishing and ClickFix-style routing pattern: the PDF itself is inert, while the linked page performs the credential prompt or fake verification.
  • 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/431946152/free-robux-2021-game-hack In PDF document text
    • https://www.kaojen.com.tw/upload/files/is-minecraft-free-on-ps4_GM479516143.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/minecraft-free_GM479516143.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/free-robux-captcha_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/spin-link_GM406889139.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/coin-master-free-spins-generator-no-verification_GM406889139.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/tuto-comment-hack-robux_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/robux-free-com_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/coin-master-hack-september-2021_GM406889139.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/pin-robux-free-2021_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/how-to-get-real-robux_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/ssunset-city-how-to-get-free-money-roblox_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/coin-master-hack-spin-ios_GM406889139.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/how-to-block-someone-on-coin-master_GM406889139.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/coin-master-hack-ios-download_GM406889139.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/robux-hack-cydia_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/free-minecraft-alt-generator_GM479516143.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/free-vine-crown-for-roblox_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/master-coin-free-spin_GM406889139.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/roblox-pc-hack-2021_GM431946152.pdfIn PDF document text
    • https://www.kaojen.com.tw/upload/files/coin-master-free-spins-hack_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
font_00_sfnt_off00002e8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2E8D 21196 bytes
SHA-256: c6c449bfd8575096cd17a7a95d822f09f4b3149e1fe383f8bd42fdb74dd0c53b
font_01_sfnt_off00005ca4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5CA4 19116 bytes
SHA-256: bd102244ffb40c6add567cd3640126a26b927334c4b0bdc73f6a542841550b4a

Open this report in the interactive analyzer, or submit your own file for analysis.