Malicious PDF — malware analysis report

Static analysis result for SHA-256 195fad9941ff1ea3…

MALICIOUS

PDF

71.2 KB Created: 2021-03-31 05:16:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: f4736ce185452025ede0c30eb10648f8 SHA-1: f91d2709e0868ef09778938fe762b3be09ce2d33 SHA-256: 195fad9941ff1ea36210512c1b8364eefdf817984919f6bd206b994c95195977
244 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many pointing to external PDF files hosted on disposable domains or potentially malicious redirectors. This behavior is indicative of a link farm, often used for SEO manipulation or to distribute further malicious content. ClamAV and ML classifiers also flagged this PDF as malicious, supporting the phishing/trojan classification.

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
  • 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://crophysi.ru/award?keyword=complexity+of+all+sorting+algorithms+pdf In PDF document text
    • https://static.s123-cdn-static.com/uploads/4465403/normal_5feb9ede8b192.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490523/normal_6036e28338aad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4477651/normal_6016bac7998be.pdfIn PDF document text
    • https://mujolimu.weebly.com/uploads/1/3/4/8/134868529/7161944.pdfIn PDF document text
    • https://rizebilawi.weebly.com/uploads/1/3/0/8/130814716/ribemujepusuku.pdfIn PDF document text
    • https://bizekexejanagiv.weebly.com/uploads/1/3/4/5/134593847/botixaresaripelo.pdfIn PDF document text
    • https://vofesoxofibebup.weebly.com/uploads/1/3/4/9/134900141/fifopuwib-wejapis-pisurojuxe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454161/normal_600c39069ab5f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465701/normal_600c6ca2e4cb0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481852/normal_6009feb54042e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4401732/normal_5fef6bbaddfa9.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4373261/normal_5fdf464ccd502.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384142/normal_6007a7aba1fbd.pdfIn PDF document text
    • https://tolirufatava.weebly.com/uploads/1/3/4/8/134879039/6b4a27c.pdfIn PDF document text
    • https://nufewaxitobazat.weebly.com/uploads/1/3/4/7/134748461/sipadifezeviduloga.pdfIn PDF document text
    • https://bukuduribo.weebly.com/uploads/1/3/1/4/131454389/pipubasaj-wufazo-pomosuxabaranan.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4500895/normal_603d25ce2f071.pdfIn PDF document text
    • https://rokubupudila.weebly.com/uploads/1/3/1/8/131856034/7498949.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/jepinebawo/tedazemamafenanovomet.pdfIn PDF document text
    • https://s3.amazonaws.com/vabedafozo/76300454832.pdfIn PDF document text
    • https://s3.amazonaws.com/gotenukevepunin/46719159519.pdfIn PDF document text
    • https://s3.amazonaws.com/zozuxukoxo/devex.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_off0000d94a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD94A 5528 bytes
SHA-256: 2195ef1b38e8a9315b576720dfab5211c423bd33df44d12ce13e89a129e998a9
font_01_sfnt_off0000ebf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF5 10260 bytes
SHA-256: b2072978cbf6211d130f602182e38c343897fdec0bb5b3ffd38c524bedc55b61