Malicious PDF — malware analysis report

Static analysis result for SHA-256 559c9a2252dd6a86…

MALICIOUS

PDF

44.8 KB Created: 2020-07-31 04:57:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3309183e4a1c19a90ae53e0d4b96b56d SHA-1: 145cda98360a4ae2084f8c4854b7a7fed40ae379 SHA-256: 559c9a2252dd6a86a24a949bd96275f6325a5c2c69f00308a80f081cee5cb44a
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, many of which point to a link farm hosted on cdn.shopify.com, and one critical link to a known malicious redirector at ttraff.ru. The document body, though heavily obfuscated, contains text related to 'brain teasers book pdf', suggesting a lure to entice users to click on the malicious links. The ML classifier also strongly flagged this PDF as malicious.

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=brain+teasers+book+pdf
    • http://files.radicalrootsherbs.com/uploads/1/3/2/6/132695280/47f6e.pdf
    • http://files.studioplumpiano.com/uploads/1/3/1/3/131383497/70178f76b.pdf
    • http://files.yasmeenalawadi.com/uploads/1/3/2/6/132682233/nakomaselip-pupomaw.pdf
    • https://cdn.shopify.com/s/files/1/0434/2513/6792/files/dekisodutekezep.pdf
    • https://cdn.shopify.com/s/files/1/0430/9535/9642/files/90973787090.pdf
    • https://cdn.shopify.com/s/files/1/0431/9779/2420/files/fuzowezupef.pdf
    • https://cdn.shopify.com/s/files/1/0438/8120/1819/files/20700702140.pdf
    • https://cdn.shopify.com/s/files/1/0429/3260/0985/files/zovutuzere.pdf
    • https://cdn.shopify.com/s/files/1/0432/5844/5979/files/kewekikejolaremejorefebox.pdf
    • https://cdn.shopify.com/s/files/1/0432/0781/9422/files/72127252605.pdf
    • https://cdn.shopify.com/s/files/1/0432/2449/8333/files/6132529685.pdf
    • https://cdn.shopify.com/s/files/1/0428/3239/6447/files/nilopagunamosebo.pdf
    • https://cdn.shopify.com/s/files/1/0437/2371/8805/files/palovadiruzepekalofuv.pdf
    • https://cdn.shopify.com/s/files/1/0427/3097/9495/files/71952759081.pdf
    • https://cdn.shopify.com/s/files/1/0428/6794/9724/files/62736193683.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_off0000716f.bin
aa34b42fc993da11a16bb9678c9597724b78bde879d7556a6b40cb126f954eaa
pdf-font-stream PDF embedded font (sfnt) at offset 0x716F 5044 bytes
font_01_sfnt_off00008297.bin
66ee51751f9ca33a951fd109e65c5da578956aca4cff1f15e995932c25fba3e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x8297 10484 bytes