Malicious PDF — malware analysis report

Static analysis result for SHA-256 7556337d40a87eff…

MALICIOUS

PDF

42.8 KB Created: 2021-05-17 06:40:10 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 25452b40657fb8aebebdce0dc5747602 SHA-1: 93da85040a82ae8fc3daa44f57da997f45a3bbb2 SHA-256: 7556337d40a87eff600ff493b43a0a6129eeab99ed30a8921c90cb6981d0d9e3
160 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains multiple links to external websites, including a known malicious redirector infrastructure. The document body and embedded links suggest a lure for game-related cheats or generators, aiming to direct users to potentially malicious content. The presence of embedded URLs and the ML classifier's high confidence score indicate a malicious intent to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://netcdn.xyz/app/431946152/roblox-pics-game-hack In PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/play-coin-master-for-free_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-robux-real-working_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-hacks-no-downloading_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/hack-coin-master-download-ios_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-ios-2021_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-coins-free_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/how-to-get-free-coins-and-spins-on-coin-master_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/roblox-hacked-version-download_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-coins-cheat_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-robux-groups-2021_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/minecraft-free-minecraft_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-mods-for-minecraft-pe_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-link-today-twitter_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/classic-minecraft-net-hacks_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/how-to-get-free-robux-by-playing-games_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/is-minecraft-free-on-nintendo-switch_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/www-claim-gg-to-earn-free-robux_GM431946152.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/is-there-a-free-version-of-minecraft_GM479516143.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/free-coins-and-spins-for-coin-master_GM406889139.pdfIn PDF document text
    • https://vosco.vn/uploads/vosco.vn/files/coin-master-free-spins-glitch_GM406889139.pdfIn PDF document text
    • https://www.roblox.comIn 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_off000049a3.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x49A3 25812 bytes
SHA-256: f6ba0c63952eafc45475905b51ffa635daa9e7338246107baeb0acd6a2914dee
font_01_sfnt_off000085b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x85B1 18060 bytes
SHA-256: 4ad043eb0dd1568e4a2653429ea485ab96dada409891d91a29e15aee7c370b08