Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d6106199b1dcaef…

MALICIOUS

PDF

41.1 KB Created: 2020-08-19 16:06:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0a6728b8518a8ce12d9b803d598a3c76 SHA-1: 9ece3b8072df9c86c0f3612cda486f16ff93ef35 SHA-256: 5d6106199b1dcaef861825e005c5f4d83260eea538f54d6895b578ea6e31339a
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though partially corrupted, contains text related to 'decimal problems 6th grade worksheet pdf' and the malicious URL, suggesting a lure to disguise the malicious intent. 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.cc/pify?keyword=decimal+problems+6th+grade+worksheet+pdf
    • http://kenola.jeremymather.com/uploads/1/3/0/7/130739415/4abc91a.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0441/0903/7720/files/domanogitarufiwufi.pdf
    • https://cdn.shopify.com/s/files/1/0435/5306/3063/files/excel_vlookup_formula_example.pdf
    • https://cdn.shopify.com/s/files/1/0428/0667/3575/files/boletejebukaj.pdf
    • https://cdn.shopify.com/s/files/1/0431/4805/0586/files/durga_saptashati_sloka_in_sanskrit.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/21154843933.pdf
    • https://cdn.shopify.com/s/files/1/0428/8570/9987/files/luvenedebatijobodus.pdf
    • https://cdn.shopify.com/s/files/1/0427/7056/3239/files/breviarios_fce.pdf
    • https://cdn.shopify.com/s/files/1/0427/9956/2911/files/40437770838.pdf
    • https://cdn.shopify.com/s/files/1/0450/7975/6963/files/difference_between_informal_and_formal_report.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_off0000610d.bin
642699aeadd9a08b3156799aa0a4ded7c5b006123711db0826ed0b2973db72a3
pdf-font-stream PDF embedded font (sfnt) at offset 0x610D 6016 bytes
font_01_sfnt_off0000756d.bin
451a943498f5452b693678540b8d57a934fe2fd5379aba4b846020732def7aa9
pdf-font-stream PDF embedded font (sfnt) at offset 0x756D 10072 bytes