Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb519cc243c519d8…

MALICIOUS

PDF

46.0 KB Created: 2020-03-29 01:59:15 +02:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-24
MD5: b775229b56ceba2a780412c03614fc02 SHA-1: a1e849b6f6cd78f0aa789427c3e77ef6481bcca2 SHA-256: fb519cc243c519d8234be453cdc85639854204862d0fe143b6f9b99a044468ba
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a large number of external links, a technique often used for SEO manipulation or to redirect users to malicious sites. The heuristic 'PDF_SEO_LINK_FARM' specifically identifies this behavior. The ML classifier also strongly indicated maliciousness. The document body contains metadata related to GNS3 and wkhtmltopdf, but the primary malicious activity appears to be the mass distribution of external links.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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 http://host115.carmichaelnl.com/uploads/1/3/0/9/130969330/130969330.html#gns3+ios+images PDF link annotation
    • http://yourprobank.com/uploads/1/3/0/4/130478210/00f69877a.pdfIn PDF document text
    • http://www.woodbrothers-creations.com/uploads/1/3/0/2/130292013/zugomamujukidij-jiroluduzede-rojujifiwedim-jajegazo.pdfIn PDF document text
    • http://flex87.pleasingfood.com/uploads/1/3/0/9/130969915/3d203dec.pdfIn PDF document text
    • http://www.tpvantransport.com/uploads/1/3/0/8/130813931/6604879.pdfIn PDF document text
    • http://webmail.annaydawson.com/uploads/1/3/0/2/130289344/denevezowuvukilitoz.pdfIn PDF document text
    • http://reachandclean.org/uploads/1/3/0/6/130604723/bezekivilupipa_rowevuxukukito_tiron.pdfIn PDF document text
    • http://www.randomgraphix.co.nz/uploads/1/3/0/6/130605179/8663413.pdfIn PDF document text
    • http://goodsky.news/uploads/1/3/0/6/130605255/23a825b212032.pdfIn PDF document text
    • http://panthersgame.dadgifts.us/uploads/1/3/0/6/130639027/2443798.pdfIn PDF document text
    • http://kellytarnowski.com/uploads/1/3/0/5/130590431/boruwojuz_sixuzavu.pdfIn PDF document text
    • http://www.returntosenderid.com/uploads/1/3/0/9/130969298/dodajoxojutal-sovamuluninix.pdfIn PDF document text
    • http://mcgutter.com/uploads/1/3/0/4/130488750/nodipuxojuwidijam.pdfIn PDF document text
    • http://elevageshagyari.com/uploads/1/3/0/9/130969500/47b9a683c17.pdfIn PDF document text
    • http://fromfostertofabulous.com/uploads/1/3/0/7/130774962/gediwulowar.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text

Extracted artifacts 1

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000088d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x88D0 9036 bytes
SHA-256: 29a492a345c9c640cb63b12fed53a461db71f703f36cf1c587c97c80e160a7e1