Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c135d57bd05ba02…

MALICIOUS

PDF

43.2 KB Created: 2021-05-12 12:07:59 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 3a9db88130a64d6dc79fd73b8916fa32 SHA-1: 664b5c2a47bb615cb3945d8c60c91347b6353cb5 SHA-256: 1c135d57bd05ba02de8f6d35c22a94798a6f734a1d51ba4b781d6bcf93df0e4b
220 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a critical heuristic firing for a game hack redirector lure, pointing to a malicious URL. It also includes a large number of links, many of which are to benign-looking PDFs, suggesting a link farm or SEO poisoning tactic. The document body, though heavily obfuscated, contains references to 'Roblox Hack Me' and the malicious URL, reinforcing the lure. No scripts were extracted, but the primary attack vector appears to be directing users to malicious infrastructure via a deceptive link.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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 https://netcdn.xyz/app/431946152/roblox-hack-me-game-hack In PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/free-rare-cards-for-coin-master-christmas_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/minecraft-apk-114-4_GM479516143.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/roblox36com-free-robux_GM431946152.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/how-to-get-free-spins-on-coin-master-2021_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-free-spins-link-download_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/free-robux-generator-without-human-verification_GM431946152.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/minecraft-xbox-one-edition-digital-code-free_GM479516143.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/official-coin-master-free-spins_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/como-hackear-juego-coin-master_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/free-robux-real_GM431946152.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-hack-version-ios_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/free-robux-generator-for-kids_GM431946152.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-free-spins-hack-iphone_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/free-coins-coin-master-hack_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-hack-apk-with-fb-login-2021_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/free-robux-without-doing-anything_GM431946152.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-links-2021_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/free-robux-codes-generator-no-verification_GM431946152.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/coin-master-free-coins-and-spins-app_GM406889139.pdfIn PDF document text
    • https://www.heathcote.staffs.sch.uk/admin/ckfinder/userfiles/files/how-to-earn-free-stars-on-coin-master_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
stream_003_off00004db5.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4DB5 24612 bytes
SHA-256: 3f303ab92001706e0f98d614d93f7e2a8ae07938e66ad929b6df1400a0ccfb1f
font_01_sfnt_off00008639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8639 18376 bytes
SHA-256: aef395c884b1121fa113f915db4056a7b0027cd471dc4d96a5cdd03c50f60cf3