Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8258c9c042d6ae3…

MALICIOUS

PDF

77.5 KB Created: 2021-04-02 04:40:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-07
MD5: 560e6bc8f8cc915c6b2b78d9bba32fc3 SHA-1: 9a455f6a7248acac332117319f3e0d4ce5c1283c SHA-256: c8258c9c042d6ae33eac2be0a20f77fecaf462a0261cca77da727bc7082012db
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or SEO manipulation tactic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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
  • 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.
  • 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 https://baarspo.ru/strik?utm_term=how+much+is+autozone+employee+discount PDF link annotation
    • https://cdn.sqhk.co/zifixanuk/gijdhdF/50901394987.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466398/normal_603f875b1cfe3.pdfIn PDF document text
    • https://wizugelavuri.weebly.com/uploads/1/3/5/3/135325487/fedesidoxolawi.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380083/normal_601392952f4d5.pdfIn PDF document text
    • https://cdn.sqhk.co/lojibuwe/dsljhid/pro_vs_college_football_coach_salary.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452845/normal_600f155d53237.pdfIn PDF document text
    • https://mumixiginuwogi.weebly.com/uploads/1/3/4/7/134752923/ginuzi.pdfIn PDF document text
    • https://libigidibejaxa.weebly.com/uploads/1/3/3/9/133997225/6931372.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480898/normal_6040ae913ac43.pdfIn PDF document text
    • https://cdn.sqhk.co/xivovido/jKQiehe/dipiwigokatisuvugab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480584/normal_6047830cf26c5.pdfIn PDF document text
    • https://cdn.sqhk.co/jasolugud/Xehf3hh/18042111071.pdfIn PDF document text
    • https://cdn.sqhk.co/wezufunin/yZBibgc/56704458144.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/nitizobuv/to_perform_the_assay_of_ammonium_chloride.pdfIn PDF document text
    • https://s3.amazonaws.com/tobito/catcher_in_the_rye_soundtrack_project.pdfIn PDF document text
    • https://f64a1a0a-debf-4843-a838-a34c0cae0f4a.filesusr.com/ugd/89602e_26e476f7b432426397253afd51e08241.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/617e32e0-f4fa-4457-bdd7-07deeef08513/how_to_stubbornly_refuse_to_make_yourself_miserable.pdfIn PDF document text
    • https://2a4b29e6-a790-453e-81e7-e8b9caf2c27b.filesusr.com/ugd/bf0735_97f2e8eec2fe4de08de7a14b0bce6604.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/rujabepifar/miller_syncrowave_250_manual.pdfIn PDF document text
    • https://s3.amazonaws.com/rogugagatuf/11199184284.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7c23b122-a8f8-4f66-a827-cf6a75f59171/86603092934.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_off0000ef59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF59 5420 bytes
SHA-256: e506c5c49904f4cd8ab9eed782ff9573127c670823593fc84be7b8775a344a77
font_01_sfnt_off000101c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C6 11324 bytes
SHA-256: ead082645152c433b34904373c2112e1d9fabd43121d094164257a55321dc720