Malicious PDF — malware analysis report

Static analysis result for SHA-256 6887881b6d4c3b3a…

MALICIOUS

PDF

34.7 KB Created: 2020-08-09 17:31:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9ee22a0c7e75e332aae6e686cb1c8689 SHA-1: 50b6e770ee352206311c5ce6af7d21ce91dd8d4f SHA-256: 6887881b6d4c3b3a73cbc375a8c34113902c12a03563ac14dfe67af2e46cb359
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to external PDF files hosted on various domains. One critical heuristic identified a link to known malicious redirector infrastructure at 'https://ttraff.ru/pify?keyword=dupre+adeste+fideles+pdf'. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains the same malicious URL, suggesting a link farm or SEO poisoning attack designed to redirect users to malicious content.

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.ru/pify?keyword=dupre+adeste+fideles+pdf
    • http://files.bigskyadventuretours.com/uploads/1/3/1/4/131483719/tevadolitiko.pdf
    • http://files.theparishofstaugustine.com/uploads/1/3/2/7/132740352/wufagideweji_jisisozin_sadagub_dajitomod.pdf
    • http://files.alma-cac.org/uploads/1/3/0/9/130969811/funevo.pdf
    • http://files.dreambignationinc.com/uploads/1/3/1/0/131070342/1e4e2cb99.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0434/5472/6310/files/51864298471.pdf
    • https://cdn.shopify.com/s/files/1/0428/5664/4774/files/93409350935.pdf
    • https://cdn.shopify.com/s/files/1/0428/8937/9993/files/98181532423.pdf
    • https://cdn.shopify.com/s/files/1/0433/2758/6457/files/xudamuvuvopexisulesabula.pdf
    • https://cdn.shopify.com/s/files/1/0435/4015/2475/files/sefulomazo.pdf
    • https://cdn.shopify.com/s/files/1/0432/3013/4427/files/8648133672.pdf
    • https://cdn.shopify.com/s/files/1/0435/1809/9615/files/79713158737.pdf
    • https://cdn.shopify.com/s/files/1/0429/8699/5863/files/rulopizimafanapunet.pdf
    • https://cdn.shopify.com/s/files/1/0429/2981/5705/files/80698917524.pdf
    • https://cdn.shopify.com/s/files/1/0430/0609/9605/files/star_wars_the_force_unleashed_cheats.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000048a4.bin
2ff623b62966137c7a5dd84d5d0e8c29b20e7b14d769ab792f4ff30ede9291ac
pdf-font-stream PDF embedded font (sfnt) at offset 0x48A4 5032 bytes
font_01_sfnt_off000059d5.bin
72113a303c78fc249912280c650c206cf590d54d3c03b2ef2823fa6b6612f8ea
pdf-font-stream PDF embedded font (sfnt) at offset 0x59D5 10244 bytes