Malicious PDF — malware analysis report

Static analysis result for SHA-256 77816933fb4de40e…

MALICIOUS

PDF

40.0 KB Created: 2020-08-18 19:01:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 4faefd3e0a3aa8a027991b94b2b0ff1f SHA-1: da936c0bdba5d83b39f3cd5c9764745399140aea SHA-256: 77816933fb4de40e4f74568102837e23943af80f2993b7ccf25da896618ed53f
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a high number of embedded links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains the malicious URL and appears to be a lure for users searching for specific PDF content. The ML classifier strongly indicates maliciousness, and the PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms the presence of a malicious URL.

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=nomenclatura+de+las+bacterias+pdf
    • http://texadig.customcrushfitness.com/uploads/1/3/1/3/131383264/642ea6d.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0455/2966/1605/files/thermal_breeder_reactor.pdf
    • https://cdn.shopify.com/s/files/1/0430/7917/2257/files/94793292387.pdf
    • https://cdn.shopify.com/s/files/1/0428/3911/3895/files/nedufeluti.pdf
    • https://cdn.shopify.com/s/files/1/0435/4755/8037/files/78464262196.pdf
    • https://cdn.shopify.com/s/files/1/0431/6885/8276/files/tonuvopumorelire.pdf
    • https://cdn.shopify.com/s/files/1/0430/6547/5226/files/spinal_anesthesia_for_c_section.pdf
    • https://cdn.shopify.com/s/files/1/0429/9676/0730/files/ats_socomec.pdf
    • https://cdn.shopify.com/s/files/1/0436/1220/9315/files/auto_body_repair_technology_5th_edition_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0430/8202/3061/files/85385216014.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_off00005e59.bin
f91bf4dbfe66dae9bd11248b7d47853b22ed0924ba117a07e27defb21f823ba6
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E59 5412 bytes
font_01_sfnt_off000070a1.bin
ba1f76ccdb4958728735e5322479bf76b87424a91e1b685464ddb021e9027a5c
pdf-font-stream PDF embedded font (sfnt) at offset 0x70A1 10624 bytes