Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5da1319269f1572…

MALICIOUS

PDF

80.0 KB Created: 2021-09-22 10:46:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7eb48f734618ce0e342e1405de1a07e1 SHA-1: 0cc26900fc26cf0d70e8c7a48beec994916028f3 SHA-256: c5da1319269f15725d46c49a0ba18238af3f9bd29849839e60dd2e360f10eaef
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external links, many of which point to PDF files hosted on various domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a tactic to obscure malicious intent through a network of redirecting links. The ML classifier and ClamAV detection strongly suggest malicious behavior, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://chayka-svg.ru/files/pudijo.pdf In PDF document text
    • http://gamboeng.com/assets/ckfinder/userfiles/files/61637259059.pdfIn PDF document text
    • http://dorinhawear.com/admin/fckeditor/editor/filemanager/connectors/php/fckeditor/editor/filemanager/connectors/php/userfiles/file/wilimowexikunabesax.pdfIn PDF document text
    • http://fujieshubao.com/zk/UploadFile/file/2021090902492173499.pdfIn PDF document text
    • http://dekoblickfang.de/userfiles/file/sedetapagelivulani.pdfIn PDF document text
    • http://www.dogwoodagility.nl/ckfinder/userfiles/files/pakeforud.pdfIn PDF document text
    • http://ffarchitettura.it/userfiles/files/gerumeduvelipipanatobarob.pdfIn PDF document text
    • http://ledins.lv/cms/file/87299167163.pdfIn PDF document text
    • http://cleangroupbd.com/ck/upload/files/27614588779.pdfIn PDF document text
    • http://veterinariacomportamentale.it/userfiles/files/11804970517.pdfIn PDF document text
    • http://cnmrobotics.com/files/files/fifasibozabofekef.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202109200529593846.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/161386d52643f3---82670314936.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614009149f21d---7701878631.pdfIn PDF document text
    • https://ecpa.fr/uploaded/file/tepimup.pdfIn PDF document text
    • http://buffagiuseppeinfissi.com/userfiles/files/3543737600.pdfIn PDF document text
    • https://labelmarket.eu/data/file/79605302292.pdfIn PDF document text
    • http://mama-care.com/UserFiles/file/3691106306.pdfIn PDF document text
    • http://due.pt/js/ckfinder/userfiles/files/lobirafazaxapegajom.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/selurerinabivonitiva.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/nabuvo.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/dananotijoruzukogi.pdfIn PDF document text
    • http://www.accessibilite-salle-eau.com/ckfinder/userfiles/files/manawitufizawutimama.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=gta+liberty+city+stories+free+download+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_off0000d43f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD43F 17192 bytes
SHA-256: 7fb28d54feee4cc59b020d561704f1ea9a2d64c1650241cf508636e663d45f7a
font_01_sfnt_off00010065.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10065 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001187c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1187C 10848 bytes
SHA-256: 1087b12c11f038914455f99a0f08a668bc76724316bbadbc823e7224f47dc4c1