Malicious PDF — malware analysis report

Static analysis result for SHA-256 20c301dd76cea5df…

MALICIOUS

PDF

49.9 KB Created: 2020-08-07 19:27:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f27b8bc621cc285a17d8122446abe320 SHA-1: 7b77ac5c5c6f8a8895e8a0d4665102d48389506d SHA-256: 20c301dd76cea5df10a2fa899591d5103470cf5d9d5b752d5c6e07d58a7dcf69
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one identified as a malicious redirector. The heuristic PDF_SEO_LINK_FARM indicates a link farm designed to host numerous PDF files, likely for SEO poisoning or to distribute malicious content. The ML classifier also strongly flagged this PDF as malicious. The primary attack pattern involves luring users to click on these links, which likely lead to phishing sites or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://ttraff.cc/pify?keyword=cbse+affiliation+bye+laws+2020+17+pdf
    • http://files.blockhashpodcast.com/uploads/1/3/2/6/132696117/fojizu.pdf
    • http://files.friendsfordisposal.com/uploads/1/3/1/6/131606502/4e3f97.pdf
    • http://files.mrjennings.org/uploads/1/3/0/9/130969429/9470405.pdf
    • https://cdn.shopify.com/s/files/1/0429/8909/3018/files/kovonutibo.pdf
    • https://cdn.shopify.com/s/files/1/0428/8331/7926/files/chromatic_harmonica_lessons.pdf
    • https://cdn.shopify.com/s/files/1/0429/1634/8057/files/68433371361.pdf
    • https://cdn.shopify.com/s/files/1/0435/9228/6363/files/bidodekonevapujanarenidum.pdf
    • https://cdn.shopify.com/s/files/1/0432/0962/1665/files/vomisagel.pdf
    • https://cdn.shopify.com/s/files/1/0428/9898/1030/files/american_colonies_alan_taylor_free.pdf
    • https://cdn.shopify.com/s/files/1/0429/5308/0991/files/36265766030.pdf
    • https://cdn.shopify.com/s/files/1/0435/3998/8648/files/aruba_weather_forecasts.pdf
    • https://cdn.shopify.com/s/files/1/0435/4444/5082/files/91955691825.pdf
    • https://cdn.shopify.com/s/files/1/0432/4527/3251/files/skull_candy_mp3.pdf
    • https://cdn.shopify.com/s/files/1/0428/7938/5766/files/41184454936.pdf
    • https://cdn.shopify.com/s/files/1/0434/1478/2104/files/15012245959.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000082c8.bin
b439531b03c3ebc3af4608f51301d907534540aca41f95e3d67b0bcd6ebf84c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x82C8 5584 bytes
font_01_sfnt_off00009601.bin
90cc5acbb5b453a9d36df7fb4d4a5a83bb42394136290319a9f9082ed01f5e6f
pdf-font-stream PDF embedded font (sfnt) at offset 0x9601 10696 bytes