Malicious PDF — malware analysis report

Static analysis result for SHA-256 04b26e8ebfb51d66…

MALICIOUS

PDF

34.6 KB Created: 2021-06-25 18:02:56 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-11-23
MD5: bab2ca5a1a0c01118ec35ce097071f15 SHA-1: 5c62cf1773729859b64afbcea47ff846704bb135 SHA-256: 04b26e8ebfb51d66d1fede7a4272e936a14191715c0b5a5e9b789db7e9d779d4
220 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains multiple links to a redirector URL that appears to be part of a link farm, aiming to lure users into clicking on potentially malicious content related to game hacks and free currency. The document's structure and embedded links suggest it is designed to drive traffic to external sites, likely for phishing or malware distribution. No scripts were extracted, but the PDF's nature as a lure is strongly indicated by the heuristics.

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.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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.co/app/431946152/free-robux-no-sign-in-game-hack In PDF document text
    • http://achauco.vn/public/upload/files/free-coin-master-coins-and-spins_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/is-roblox-free-on-pc_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-cheats-dlls_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-hacks-account_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/how-to-get-free-robux-no-survey-no-online-generator_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/coin-master-hack-online-without-human-verification_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/coin-master-daily-free-spins-link-app-download_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/coin-master-free-spins-link-hack_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/free-character-in-roblox-2021_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/how-to-download-a-swearfree-roblox-speech-plugin_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/free-realistic-minecraft-texture-packs_GM479516143.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/roblox-stands-online-item-cheat_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/free-robux-codes-2021-not-used_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/cool-free-minecraft-skins_GM479516143.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/como-hackear-juego-coin-master_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/how-to-make-your-own-hacks-for-roblox_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/download-roblox-mod-free-robux_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/free-robux-website_GM431946152.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/coin-master-free-spin-best-link_GM406889139.pdfIn PDF document text
    • http://achauco.vn/public/upload/files/break-free-dangerous-woman-tour-studio-version-roblox-music-code_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
font_00_sfnt_off000030fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x30FC 22364 bytes
SHA-256: 0e91abaefc82d4fa9cf7856a634456b2c57ad620de5edd19421171899cbffdf4
font_01_sfnt_off000062e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x62E0 18836 bytes
SHA-256: 44df7ba131cc94ddab9dd0f662631bb5faca0030a80f84e3214b51cec1ffe28c