Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb10d7767c8b4526…

MALICIOUS

PDF

40.2 KB Created: 2020-07-27 21:44:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1bee82326c3d94586a556df0aaae1706 SHA-1: c73edcb3c2809d15ad1240149a1a83701a96462e SHA-256: cb10d7767c8b4526377d9172255e1bc753e8cbdae0cdef8dfea8c7665f9abe4d
152 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and heuristic analysis. It contains a large number of embedded links, many pointing to Shopify domains, suggesting a link farm or SEO manipulation tactic. One critical heuristic identified a link to a known malicious redirector at 'ttraff.com'. The document body, though heavily obfuscated, appears to be a worksheet lure.

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.com/pify?keyword=punctuation+marks+worksheet+grade+4
    • http://files.rubbishclearanceleeds.com/uploads/1/3/1/8/131871633/6019648.pdf
    • http://files.bgiplus.com/uploads/1/3/1/3/131379615/c9036433.pdf
    • http://files.lilys4paws.com/uploads/1/3/0/8/130874169/2708dd4e31.pdf
    • http://files.rubbishclearanceleeds.com/uploads/1/3/1/8/13
    • https://cdn.shopify.com/s/files/1/0433/0936/7461/files/joliset.pdf
    • https://cdn.shopify.com/s/files/1/0427/5778/3718/files/61480189610.pdf
    • https://cdn.shopify.com/s/files/1/0427/7560/9510/files/bozur.pdf
    • https://cdn.shopify.com/s/files/1/0429/9977/5381/files/26828117944.pdf
    • https://cdn.shopify.com/s/files/1/0429/2981/5705/files/zonagi.pdf
    • https://cdn.shopify.com/s/files/1/0430/6763/7917/files/vexodadixibiso.pdf
    • https://cdn.shopify.com/s/files/1/0432/6552/3870/files/38029336528.pdf
    • https://cdn.shopify.com/s/files/1/0433/0936/7454/files/5042432178.pdf
    • https://cdn.shopify.com/s/files/1/0431/4365/9677/files/68721536593.pdf
    • https://cdn.shopify.com/s/files/1/0431/8350/5570/files/7287311612.pdf
    • https://cdn.shopify.com/s/files/1/0430/8012/2532/files/70249684914.pdf
    • https://cdn.shopify.com/s/files/1/0435/3074/8072/files/57196320750.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_off000060f7.bin
5c9d9dfc371ff38ea74fe3636f7f6a80b0ea80565eabbee7fffccf5962c72785
pdf-font-stream PDF embedded font (sfnt) at offset 0x60F7 5448 bytes
font_01_sfnt_off00007360.bin
b7840a50831058dd7f59a15a6f4d1cc202ddd0aa5f76abc02a4919c3c9faebc1
pdf-font-stream PDF embedded font (sfnt) at offset 0x7360 9544 bytes