Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8177ebd30895fae…

MALICIOUS

PDF

85.8 KB Created: 2021-09-22 11:34:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: fd62b78edf78eb82c3f75febd4ea0d9e SHA-1: ece67edbd7aad0d6309c9a7c20c9a0dc223c29ff SHA-256: f8177ebd30895fae7c83a9b55cc13f11e97b523217bd80a48738e74e1f78a8ce
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports the interpretation of this file as a distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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 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 http://rrarental.org/upload/file/tefemejon.pdf In PDF document text
    • http://driscollandgibson.com/images/edit_images/file/68293068901.pdfIn PDF document text
    • http://verypool.cn/images/upload/File/padewobufutenenoz.pdfIn PDF document text
    • http://pinzimoniofiumicino.eu/userfiles/files/jusotofatugum.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1614405795556c---74808918756.pdfIn PDF document text
    • https://wecareprogram.org/images/file/20093571874.pdfIn PDF document text
    • https://thebillionbottom.com/business_school/uploads/file/48324521471.pdfIn PDF document text
    • https://iringmalaysia.com/ckfinder/userfiles/files/59760238424.pdfIn PDF document text
    • http://polletnv.be/uploads/files/7920070641.pdfIn PDF document text
    • https://hydratrend.com/application/third_party/ckfinder/userfiles/files/64994410410.pdfIn PDF document text
    • http://stellarp.com/userfiles/files/rotimopenesopawima.pdfIn PDF document text
    • http://hengtongblower.com/d/files/dawiw.pdfIn PDF document text
    • https://valerart.com/ckfinder/userfiles/files/mezijus.pdfIn PDF document text
    • https://almudenafernandez.co/ckfinder/userfiles/Files/79168422283.pdfIn PDF document text
    • https://hum639hb2-hh38.com/contents/files/95521152255.pdfIn PDF document text
    • http://gidaero.com/upload/fckeditor/file/23724974923.pdfIn PDF document text
    • http://plusdesignwebsite.com/userfiles/file/bodoririkuvoxof.pdfIn PDF document text
    • http://kleinschadenexpert.com/userfiles/file/17859379826.pdfIn PDF document text
    • https://restaurant-kamkok.fr/img/Data/file/xafode.pdfIn PDF document text
    • http://nattuvaartha.com/assets/ckfinder/core/connector/php/uploads/files/tipamufuvejatok.pdfIn PDF document text
    • http://ptairsupply.com/userfiles/file/kivekudejuladaxu.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3ec8ead16---wasobumujupobegedobipuzej.pdfIn PDF document text
    • http://telek-trans.hu/editor_up/xozinopekinel.pdfIn PDF document text
    • https://holyfamilyhospitals.com/ckfinder/userfiles/files/73415481260.pdfIn PDF document text
    • http://www.jfac.kr/ckfinder/userfiles/files/91766870250.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=core+apps+androidPDF link annotation
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eae5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAE5 10272 bytes
SHA-256: 57fd305c696ae3af79c83ccdc89fa4a917b1b26e648076e7636f6cafe8ed493a
font_01_sfnt_off00010215.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10215 18428 bytes
SHA-256: 39f36aa46ead34c13dc619756e840a92a6e508672a77818c9b72cd2e40136a18
font_02_sfnt_off0001316c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1316C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1