Malicious PDF — malware analysis report

Static analysis result for SHA-256 efe50575269ab3e4…

MALICIOUS

PDF

42.8 KB Created: 2021-05-19 18:37:12 +07:00 Authoring application: wkhtmltopdf 0.12.6 (via Qt 4.8.7)
MD5: 3ad97cbf70a80b55d82428a1a8620cd2 SHA-1: bd08fe72d3819e290a00632a8ed1c1a147b9a054 SHA-256: efe50575269ab3e49dcf82f3fbcfad5de43a6014ef5ce9c4f6b9be8add376fcb
102 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of external links, many with SEO-like slugs related to popular games and free currency. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of such links, suggesting a link farm or scam operation. The presence of a 'download button' heuristic further supports the lure of clicking these links for a perceived benefit. No scripts were extracted, but the primary attack vector appears to be directing users to malicious or scam websites via embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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/coin-master-free-coins-and-spins-2021-game-hack
    • https://www.knjizara-harfa.rs/files/coin-master-free-spins-app_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/how-to-make-your-own-minecraft-pe-server-for-free_GM479516143.pdf
    • https://www.knjizara-harfa.rs/files/coin-master-free-spins-2021-app_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/do-robux-generators-work_GM431946152.pdf
    • https://www.knjizara-harfa.rs/files/free-robux-no-gift-card_GM431946152.pdf
    • https://www.knjizara-harfa.rs/files/coin-master-daily-free-spins-link-app_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/unlimited-robux-2021_GM431946152.pdf
    • https://www.knjizara-harfa.rs/files/coin-master-daily-spins-and-coins_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/free-robux-only-1-step_GM431946152.pdf
    • https://www.knjizara-harfa.rs/files/coin-master-hack-tool-download_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/minecraft-hack-download_GM479516143.pdf
    • https://www.knjizara-harfa.rs/files/hack-coin-master-for-free_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/free-robux-safe_GM431946152.pdf
    • https://www.knjizara-harfa.rs/files/coin-master-32-mod-hack-unlimited_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/coin-master-hack-download-apk_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/100-free-spins-coin-master_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/free-daily-spin-coin-master-game_GM406889139.pdf
    • https://www.knjizara-harfa.rs/files/how-to-get-free-robux-fast-and-easy_GM431946152.pdf
    • https://www.knjizara-harfa.rs/files/how-to-get-a-free-minecraft-server_GM479516143.pdf
    • https://www.knjizara-harfa.rs/files/hack-de-coin-master_GM406889139.pdf
    • http://en.wikipedia.org/wiki/MIT_License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00004c81.bin
b3cd521defc91c8ba26f5829b35575d190ac2102d62f7aa320beab699c03f67b
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x4C81 24328 bytes
font_01_sfnt_off0000843b.bin
9b9248072d2421e664493d6d5ab14406474bc62db1d786ff94b6c1680f0f8261
pdf-font-stream PDF embedded font (sfnt) at offset 0x843B 18460 bytes