Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd3e5da81585cb58…

MALICIOUS

PDF

57.7 KB Created: 2020-03-29 14:40:48 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-04
MD5: 12e83714d705da282c24ec7bcea6bafa SHA-1: 48d1c068d1da0ebffb3f8080ff2b49061f396065 SHA-256: fd3e5da81585cb58e998f0e965cd2a0586c46746f7f18cb99de90fb5dc0840cd
136 Risk Score

Malware Insights

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

The PDF contains a large number of external links to other PDF files hosted on various domains. This technique is often used for SEO spam or to distribute further malicious content. The ML classifier strongly indicated maliciousness, and the presence of a link farm heuristic further supports this. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 5

  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://74-123-72-35.mgwnet.com/uploads/1/3/1/4/131437508/131437508.html#clasificacion+de+los+problemas+de+aprendizaje+pdf PDF link annotation
    • http://thebuntruck.com/uploads/1/3/0/2/130289218/122504.pdfIn PDF document text
    • http://jonahandsophiebnaimitzvah.com/uploads/1/3/0/7/130740419/863139.pdfIn PDF document text
    • http://laurenandersonrealty.com/uploads/1/3/0/6/130605393/5093748.pdfIn PDF document text
    • http://brandimorganlaw.com/uploads/1/3/0/5/130550750/2dbbc0d.pdfIn PDF document text
    • http://licorporatelawyer.com/uploads/1/3/0/9/130969281/ferotefedawef.pdfIn PDF document text
    • http://fieldcompact.com/uploads/1/3/0/8/130873877/jizaboru.pdfIn PDF document text
    • http://cvillehomeinspection.com/uploads/1/3/0/5/130551247/c40da.pdfIn PDF document text
    • http://wertygardening.com/uploads/1/3/0/6/130639976/6e0f0b147fc.pdfIn PDF document text
    • http://missionvalleycondo.com/uploads/1/3/0/5/130550844/zogewiz-gigimajineloruz.pdfIn PDF document text
    • http://vrlegalstrategies.com/uploads/1/3/0/5/130550983/9684619.pdfIn PDF document text
    • http://daisywholefoods.com/uploads/1/3/0/5/130550700/mipasizitorunifisaru.pdfIn PDF document text
    • http://startertees.com/uploads/1/3/0/6/130640235/bijaga.pdfIn PDF document text
    • http://cresswellpaints.com/uploads/1/3/0/5/130539934/c2f9a68e69605d0.pdfIn PDF document text
    • http://addorganized.com/uploads/1/3/1/1/131164473/zizejiwek.pdfIn PDF document text
    • http://samvika.com/uploads/1/3/0/7/130739935/4377520.pdfIn PDF document text
    • http://demirevolution.com/uploads/1/3/0/4/130476976/6979025.pdfIn PDF document text
    • http://silvercloudstudios.com.au/uploads/1/3/1/1/131164562/8148a6c7b.pdfIn PDF document text
    • http://filmroar.com/uploads/1/3/0/3/130313643/13e3b6a2d9aa1c.pdfIn PDF document text
    • http://completehealthfoundation.org/uploads/1/3/0/6/130603835/zufazuwipenej-bixuberufu.pdfIn PDF document text
    • http://1autoabi.ee/uploads/1/3/0/4/130494636/7b9eeac1ace0d.pdfIn PDF document text
    • http://barbattu.com/uploads/1/3/0/4/130483989/5104092.pdfIn PDF document text
    • http://magnoliamerchants.com/uploads/1/3/0/4/130483766/6124797.pdfIn PDF document text
    • http://thehatpursecorporationofamerica.com/uploads/1/3/0/2/130288307/babf86862.pdfIn PDF document text
    • http://veloandcoffee.com/uploads/1/3/0/7/130739218/7eea0.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000a1fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA1FD 8964 bytes
SHA-256: fdd5f9bad66232eba856a869d6240982e22dfd25f33c63acae4b1a210d532381
font_01_sfnt_off0000c238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC238 16204 bytes
SHA-256: f31c439e28d0137206b91a151f21343900f846ed9ff070250fbe82eb1cc7da1d