Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c5d51acdb75aa33…

MALICIOUS

PDF

37.3 KB Created: 2021-07-20 00:05:35 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 3a0c119b110ab2f4f20b3ea2529e1e9d SHA-1: 673fc1740b3a9f7863c981308feaa85f33d09da1 SHA-256: 2c5d51acdb75aa336d66ff39230a743630ad53f903382bc8eb66e3a132d0ebac
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains multiple links to known malicious redirectors and lures users with promises of 'free generator' or 'game hack' content. The embedded URL http://netcdn.tw/app/406889139/free-daily-spins-coin-master-game-hack is specifically flagged as malicious. While no scripts were explicitly extracted, the PDF structure and heuristic firings indicate a malicious redirector designed to lead the user to further malicious content or downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9216

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/free-daily-spins-coin-master-game-hack In PDF document text
    • https://alimi.com.tw/upload/files/minecraft-apk-free-download-016-0_GM479516143.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/free-coin-master-coins-and-spins_GM406889139.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/coin-master-free-spin-and-coin-links_GM406889139.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/how-to-get-free-tiktok-coins_GM835599320.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/minecraft-java-free-trial_GM479516143.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/free-coin-master-coins_GM406889139.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/free-likes-for-tiktok_GM835599320.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/roblox-promo-codes-free-robux_GM431946152.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/free-robux-no-verify-2021_GM431946152.pdfIn PDF document text
    • https://alimi.com.tw/upload/files/free-printable-minecraft-coloring-pages_GM479516143.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_002_off00003197.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x3197 23044 bytes
SHA-256: 5b6bfad8c112c03b3923d55c1d528d496a0e6f3d4f260019bf6e58c2b4c7b8a1
font_01_sfnt_off00006597.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6597 2896 bytes
SHA-256: c1a618813a64314343402b2ec738fc11c4c912460a4c7ae3029924d2f9a229cd
font_02_sfnt_off00006f7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6F7C 18308 bytes
SHA-256: 55eaac4e6bbee5e06de7435d22c867d27a3c8151a397b13177f5239675c95764