Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5d35ce4f1ef51f4…

MALICIOUS

PDF

89.5 KB Created: 2021-08-01 09:58:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 45f64644eed1249d5bea8de068813565 SHA-1: e4fc17c477d1818f98079054fd515fac9a1933fe SHA-256: f5d35ce4f1ef51f4f7364f157e86aaf5c9b90b4b496f5a437403ea68abce99e5
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The embedded URLs and the nature of the heuristics point towards an attempt to lure users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://naitikfashions.com/ckfinder/userfiles/files/42755553275.pdf In PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb6687f428---xuvexivifupa.pdfIn PDF document text
    • https://centrumschoolka.pl/photos/file/zinopabeguva.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a5d4bb7059d---xadesezuvugete.pdfIn PDF document text
    • https://condominiovillage.com/userfiles/file/88535062725.pdfIn PDF document text
    • https://raptiherbal.com/ckfinder/userfiles/files/tabodorejuzemajaf.pdfIn PDF document text
    • https://birudongker.com/contents//files/tepakela.pdfIn PDF document text
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607200911aab6---wiketalisazusu.pdfIn PDF document text
    • https://talaa-obour.com/webmisr/uploadwebmisr/file/bametezesafoxuzov.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/nitokufivovaxupomewuv.pdfIn PDF document text
    • https://szekszardportal.hu/userfiles/file/mojewajipajogifinoja.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bca7be94dab---jubizupe.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/4483a8efc1f96b2c70a05bbc0494d0c2/75871048641.pdfIn PDF document text
    • http://www.dereformasenalicante.com/archivos/files/44059111115.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/fijaduwex.pdfIn PDF document text
    • http://lionsmarsala.it/userfiles/files/63173525603.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/4ailvb66afbkv60ar7slpoips3/32487275443.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/1c2ce8173db2d69d0931cd65c3e9553e/xovurisagorimew.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160aa85d2e055f---76841528670.pdfIn PDF document text
    • http://ks4073.com/file_media/file_image/file/gelusamosod.pdfIn PDF document text
    • http://surtek.biz/image/files/20150117_003816.pdfIn PDF document text
    • http://whatdwellswithin.com/file/tuzugamimigijugofeva.pdfIn PDF document text
    • http://cuatudongnhatrang.com/uploads/files/83406039752.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=maus+art+spiegelman+pdf+fran%C3%A7aisPDF link annotation
    • https://www.thc.gda.pl/ckfinder/userfiles/files/45732027608.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://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_off0000f28b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF28B 19744 bytes
SHA-256: 21c698febd72f9717898f79684a798f9dc9aa97602f4853b64ea6c85f1c48b00
font_01_sfnt_off00012443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12443 11012 bytes
SHA-256: a402be7f3fb5113bbfe92df69e97e96a5fdcaaea29bdd0111db640f190c46fbd
font_02_sfnt_off00013da3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13DA3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1