Malicious PDF — malware analysis report

Static analysis result for SHA-256 b64d4a4848f68b34…

MALICIOUS

PDF

86.9 KB Created: 2021-09-14 07:58:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 35e489d4540d1a0c57ebf582b4f53a76 SHA-1: 4633e7a86cfdf535cd0a4c2b6405d382ecf7e5d1 SHA-256: b64d4a4848f68b342f19ae824d245a39b5efdd11b7abacd9dd77a6580df17b81
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier indicating maliciousness. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates the document is a link farm on disposable hosting, with numerous distinct hosts and a high number of links. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest the document is designed to redirect users to malicious sites, likely for phishing or malware distribution. The ML_NYX_PDF_MALICIOUS heuristic strongly suggests the PDF contains malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://nexxstep.nl/userfiles/file/rafitabefugufegepenowozeg.pdf In PDF document text
    • https://wupaojichangjia.com/d/files/tefolurerinexomiton.pdfIn PDF document text
    • https://music-group-store.com/upload/files/ledabowi.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/95t3sedaus867nk03v4d54u8r3/89166924687.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/lexogis.pdfIn PDF document text
    • https://kujainspectors.com/candyticket/uploads/page_images/files/gorolupikaf.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614000502c532---62014252090.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-4/20210904124946561542.pdfIn PDF document text
    • http://lukoilmarine.com/ckfinder/userfiles/files/78369834027.pdfIn PDF document text
    • http://studioguagnoni.it/userfiles/files/jobuzaxikokofuzawofatum.pdfIn PDF document text
    • http://sushiyaslo.com/uploads/files/bolomolasiwuratewobu.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/dibexofefijidaloreta.pdfIn PDF document text
    • http://centronegozi.com/public/nipimekasogorutenumuwusew.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/87112175365.pdfIn PDF document text
    • http://alkanboya.com/files/file///petolubugimeli.pdfIn PDF document text
    • http://mega-stainlesssteel.com/uploads/image/files/29179488586.pdfIn PDF document text
    • https://majubesar.com/contents/files/26583498226.pdfIn PDF document text
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/jotepakalutegudibimexe.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/zaridowisepovetegadunu.pdfIn PDF document text
    • http://creativecoms.net/userfiles/file/jamavopo.pdfIn PDF document text
    • http://malir-naterac.info/UserFiles/File/vugiwewebibebebidafo.pdfIn PDF document text
    • http://sangiorgioautoservizi.com/userfiles/files/44494751163.pdfIn PDF document text
    • https://ezokniga.com/uploads/file/kozatimegoti.pdfIn PDF document text
    • https://bostaninsaat.com/image/files/37864025975.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=frogger+app+for+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_off0000f0a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B8 17640 bytes
SHA-256: 54a129aa29d0f5efb396e338ee7d67fa30f1a62b983f2ab40a0f3efdccc372ef
font_02_sfnt_off000136aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x136AA 10336 bytes
SHA-256: 4eaee76a854851c1f5cf392e63584708c53db89c01b952bb695e4158bfdf8bcc