Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5a59eee5bb94142…

MALICIOUS

PDF

41.1 KB Created: 2020-09-17 21:57:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-09
MD5: f97b545d40712ca4c969e106280d7a85 SHA-1: 71640582d6e3d577b5a2be2394e1d3f89f760f3b SHA-256: b5a59eee5bb94142fdef6edcea74989ed657d5f60982574f595d66acdd467b90
224 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a critical heuristic firing for a malicious redirector link, pointing to a URL that mimics a 'skills worksheet answer key'. This link is embedded within the document body, suggesting a social engineering lure. The PDF also exhibits characteristics of a link farm, with numerous embedded URLs pointing to external PDF files, likely for SEO manipulation or to host further malicious content. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • 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.
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.club/wix?keyword=skills+worksheet+cell+cycle+and+mitosis+answer+key In PDF document text
    • http://tijonif.northwestpermaculture.org/uploads/1/3/0/8/130814340/4857699.pdfIn PDF document text
    • http://files.freedivingcompetition.com/uploads/1/3/1/4/131453036/fugisaxotokisabanak.pdfIn PDF document text
    • http://putukoj.annettemontgomery.org/uploads/1/3/1/6/131606165/famega_naxesunazewe.pdfIn PDF document text
    • http://files.homecheftraining.com/uploads/1/3/1/4/131407802/benixopeza.pdfIn PDF document text
    • http://garitu.jenniferwoolcockschwartz.com/uploads/1/3/1/4/131452836/duragimek.pdfIn PDF document text
    • http://files.asaphteachingministry.com/uploads/1/3/0/8/130813601/ribifipopugas.pdfIn PDF document text
    • http://vejadipux.compassionsfireministriesinternational.org/uploads/1/3/2/7/132741099/8455974.pdfIn PDF document text
    • http://garapire.dondealmuerzo.com/uploads/1/3/0/7/130739196/9544119.pdfIn PDF document text
    • http://dopixot.circlesisters13.com/uploads/1/3/1/3/131398234/guzonamekulifuf-wowejiraxovop-bufofoliz-bajinip.pdfIn PDF document text
    • http://files.conseilscolaire-schoolcouncil.org/uploads/1/3/2/8/132815123/f9ef99aae2a6.pdfIn PDF document text
    • http://files.gopremio.com/uploads/1/3/2/6/132682076/eac43d74.pdfIn PDF document text
    • http://fagegiw.torrancerosefloat.org/uploads/1/3/0/7/130776031/xexewadugavidasewixo.pdfIn PDF document text
    • http://dibegozeb.greatervictoriatreeservice.ca/uploads/1/3/1/3/131398455/1482135.pdfIn PDF document text
    • http://files.teamgoughrealestate.com/uploads/1/3/1/6/131606360/pifafivagakuzaxisi.pdfIn PDF document text
    • http://mujanal.olneymdtravelbaseball.com/uploads/1/3/0/9/130970023/9e7b1fff82bb.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://40fafa74-991f-4e63-8183-5170911a55ac.filesusr.com/ugd/e54fc7_bd74d5d88cc54cbeb340d546424a4f27.pdf?index=trueIn PDF document text
    • https://bd184250-2e61-497d-b0b5-af9e30b05ca7.filesusr.com/ugd/30e015_6bee47afbed344c68e27a8364b57d905.pdf?index=trueIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000618e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x618E 5540 bytes
SHA-256: d0e0caa21f5202f809c9f1ed0a2d2e3823bf5be3b6818471565841eba81ff933
font_01_sfnt_off00007454.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7454 10172 bytes
SHA-256: 669d585ebb347384994848c60f036273af796cb2ff11f50711ef888a837bec49