Malicious PDF — malware analysis report

Static analysis result for SHA-256 88ef501dc07f7c41…

MALICIOUS

PDF

46.1 KB Created: 2021-06-03 08:30:36 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: 6368f5389cb068bfea4c1385bd9da538 SHA-1: fc600c07e3f219eda506418cbab5d192ff79931d SHA-256: 88ef501dc07f7c4108bb500f13f5636d80de70a97626f6538d132fb5fac18a37
122 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document contains a large number of external links, many of which point to other PDF files hosted on similar domains, suggesting a link farm designed to attract users with game-related keywords. The ML classifier strongly flagged this PDF as malicious, and the presence of a download button lure further supports a malicious intent. The document's primary goal appears to be directing users to download other files, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9797

Heuristics 5

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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.online/app/406889139/freespinandcoin-game-hack
    • https://domc.tw/upload/files/free-spins-coins-coin-master_GM406889139.pdf
    • https://domc.tw/upload/files/minecraft-build-hacks_GM479516143.pdf
    • https://domc.tw/upload/files/free-ways-to-get-robux_GM431946152.pdf
    • https://domc.tw/upload/files/blox-rewards_GM431946152.pdf
    • https://domc.tw/upload/files/coin-master-free-spins-facebook_GM406889139.pdf
    • https://domc.tw/upload/files/coin-master-hack-app-2021-download_GM406889139.pdf
    • https://domc.tw/upload/files/free-daily-spins-coin-master_GM406889139.pdf
    • https://domc.tw/upload/files/free-coin-and-spin-for-coin-master_GM406889139.pdf
    • https://domc.tw/upload/files/roblox-report-hacker_GM431946152.pdf
    • https://domc.tw/upload/files/minecraft-gun-games-free_GM479516143.pdf
    • https://domc.tw/upload/files/free-coin-spin-daily-link-net_GM406889139.pdf
    • https://domc.tw/upload/files/coin-master-free-spins-link-2021-today_GM406889139.pdf
    • https://domc.tw/upload/files/how-to-hack-roblox-accounts-on-phone_GM431946152.pdf
    • https://domc.tw/upload/files/free-robux-giveaway-live_GM431946152.pdf
    • https://domc.tw/upload/files/get-follower-tiktok-free_GM835599320.pdf
    • https://domc.tw/upload/files/como-hackear-coin-master-espaol_GM406889139.pdf
    • https://domc.tw/upload/files/coin-master-coins-free_GM406889139.pdf
    • https://domc.tw/upload/files/play-minecraft-online-free_GM479516143.pdf
    • https://domc.tw/upload/files/coin-master-free-spins-link-march-2021_GM406889139.pdf
    • https://domc.tw/upload/files/100-free-spins-coin-master-link_GM406889139.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off00004bbb.bin
bded07ab17863888b3b4fcb93d7105f08aeb70879517b528d4be632de4876f4b
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4BBB 26492 bytes
font_01_sfnt_off000088c3.bin
3fb127b764b9d10f5525bc4de5ec8316de704409ccb0cf21cff3ad8a30d11676
pdf-font-stream PDF embedded font (sfnt) at offset 0x88C3 2840 bytes
font_02_sfnt_off00009274.bin
1c693cd3c749c7deb88a93ce437f6f23953c7e7e8560ccdde2498ee9463f8dc4
pdf-font-stream PDF embedded font (sfnt) at offset 0x9274 17956 bytes