Malicious PDF — malware analysis report

Static analysis result for SHA-256 58bf3b0da81a2361…

MALICIOUS

PDF

77.6 KB Created: 2021-03-07 05:48:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 5a6e33c32f2480813561a85c452797ab SHA-1: dc7fae8926c39056c303fd67b34350b0e2b7d767 SHA-256: 58bf3b0da81a23612abf5579ad5c70345affdf586b61c9f89015d715590fa14c
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded URLs, many of which point to disposable hosting and redirectors, indicating a link farm designed to distribute malicious content or phish users. ClamAV and ML classifiers also flagged this PDF as malicious. The presence of embedded URLs and the nature of the link farm strongly suggest an attempt to redirect users to harmful sites, aligning with spearphishing attachment tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://dafemum.ru/strik?utm_term=is+15+tip+ok In PDF document text
    • https://cdn-cms.f-static.net/uploads/4377102/normal_601eb9648701c.pdfIn PDF document text
    • http://tomolijoponix.mypressonline.com/rulumup.pdfIn PDF document text
    • http://sdek-24.cc/classic_cars_for_sale_dothan_alabama_craigslistuunvd.pdfIn PDF document text
    • http://xevusezes.medianewsonline.com/present_perfect_simple_and_continuous_exercises_3_eso.pdfIn PDF document text
    • http://fekevopimibun.sportsontheweb.net/32761122143.pdfIn PDF document text
    • http://jevafurevozu.mygamesonline.org/fender_mustang_2_footswitch_schematic.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447097/normal_601eb21d6d15d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4527164/normal_603a47d7c7426.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452154/normal_5fec2361c7ba3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426942/normal_600e98b54fdef.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426087/normal_602e76bd89191.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4371790/normal_5fd1c2d02f78b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459057/normal_6013184f55801.pdfIn PDF document text
    • http://svoydvalend.xyz/knife_master_vs_fruit_hite6j2s.pdfIn PDF document text
    • http://mizizufiku.mywebcommunity.org/crochet_for_dummies_youtube.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://1de4b56a-3309-4767-83a2-f1bb1ea7c594.filesusr.com/ugd/a6e5e9_1de626c4999840ee850ec5c4f9f2c62c.pdf?index=trueIn PDF document text
    • https://6c8027e1-9878-41b3-a9ef-32ba2b6bcd02.filesusr.com/ugd/185811_0ecb2ec68f244403ba207251b7192735.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bokelur/8100244263.pdfIn PDF document text
    • https://s3.amazonaws.com/safenalavojuwu/bezipozelum.pdfIn PDF document text
    • https://01d7ec8a-e38e-4e33-8c76-1be31754498b.filesusr.com/ugd/24d943_4141fc62737c410db9023193885d86a7.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bubisifapagefe/jefulowufuvedilu.pdfIn PDF document text
    • https://6cdb29d4-22ce-4aaf-9e51-562b59d50851.filesusr.com/ugd/1b20fb_deb8de8c85cf416da1f300539368ae30.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xufoxorog/bukoxuxipibutozoxuba.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f3f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3F1 4652 bytes
SHA-256: 4d9f2b2ffe59d6d9a86214a0c57aeb3ed1bc528de6de4162ddd28e4afa3000a9
font_01_sfnt_off000103e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E9 10916 bytes
SHA-256: 9c3553cc0cffc70021cd8868d024f545a46d2488cacc84f583c9a8456d5c1294