Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9bbb0610ce748fb…

MALICIOUS

PDF

45.8 KB Created: 2021-05-14 08:53:57 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: b250fd688d343078c76b5a5182839deb SHA-1: da70e3cba554b40da9aeee789f6952761d6f69a5 SHA-256: b9bbb0610ce748fb4cf3b40f82a46edb2702489172891fa783a1cc02e7a2dbbb
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, identified by the PDF_SEO_LINK_FARM heuristic, pointing to external websites. The document body, though heavily obfuscated, contains text related to 'Free Spins Coin Master' and a URL, suggesting a lure for game-related cheats or scams. The ML classifier also flagged this PDF as malicious. The presence of multiple external links indicates an attempt to direct users to potentially harmful content or for SEO manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9432

Heuristics 4

  • 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
  • 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.xyz/app/406889139/free-spins-coin-master-2021-today-game-hack
    • http://dobrovodie.ru/images/how-to-get-free-gold-cards-on-coin-master_GM406889139.pdf
    • http://dobrovodie.ru/images/daily-free-spins-coin-master_GM406889139.pdf
    • http://dobrovodie.ru/images/daily-coin-master-free-spin-apk_GM406889139.pdf
    • http://dobrovodie.ru/images/coin-master-reward-link_GM406889139.pdf
    • http://dobrovodie.ru/images/coin-master-hack-no-verification-no-signup_GM406889139.pdf
    • http://dobrovodie.ru/images/hack-coin-master-game-download_GM406889139.pdf
    • http://dobrovodie.ru/images/free-hacks-for-coin-master_GM406889139.pdf
    • http://dobrovodie.ru/images/free-robux-websites-no-human-verification_GM431946152.pdf
    • http://dobrovodie.ru/images/play-minecraft-pocket-edition-for-free_GM479516143.pdf
    • http://dobrovodie.ru/images/free-printable-roblox-images_GM431946152.pdf
    • http://dobrovodie.ru/images/free-robux-codes-2021-not-used_GM431946152.pdf
    • http://dobrovodie.ru/images/but-link-says-free-robux_GM431946152.pdf
    • http://dobrovodie.ru/images/how-to-get-free-robux-without-human-verification_GM431946152.pdf
    • http://dobrovodie.ru/images/online-coin-master-hack-here_GM406889139.pdf
    • http://dobrovodie.ru/images/minecraft-free-download-laptop_GM479516143.pdf
    • http://dobrovodie.ru/images/spin-hack-for-coin-master_GM406889139.pdf
    • http://dobrovodie.ru/images/roblox-robux_GM431946152.pdf
    • http://dobrovodie.ru/images/hack-coin-master-with-lucky-patcher_GM406889139.pdf
    • http://dobrovodie.ru/images/robux-hacks-2021_GM431946152.pdf
    • http://dobrovodie.ru/images/how-to-get-free-robux-com_GM431946152.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00004b50.bin
7855ba8717e62de074f9321e641641f1cab7043d7ef186a8fa5adb27ca1adc90
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4B50 25264 bytes
font_01_sfnt_off00008531.bin
10d025f04f706eb71cdda4f99784df1b9ccb52e48080e43095e0398eaef6f132
pdf-font-stream PDF embedded font (sfnt) at offset 0x8531 2880 bytes
font_02_sfnt_off00008f1c.bin
fb34871543d4e589edaa7b6b6daea61d4b413826d533968c66bf721badb2f47c
pdf-font-stream PDF embedded font (sfnt) at offset 0x8F1C 18644 bytes