Malicious PDF — malware analysis report

Static analysis result for SHA-256 7da3c51c83a1e9f1…

MALICIOUS

PDF

87.8 KB Created: 2021-09-21 16:15:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 44f81accb468af69d8fe2838aa685b04 SHA-1: e33044c79632ea3a7d4463c6ea8b8505ce18d57b SHA-256: 7da3c51c83a1e9f1c50a115e4506a0de78b4c7afab7c1174902757a5bed70191
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting and are part of a link farm, indicating a phishing or redirection scheme. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of external URIs and the link farm heuristic point towards an attempt to direct users to potentially harmful external 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 https://queure.ru/uplcv?utm_term=android+sftp+client PDF link annotation
    • https://ibeguiristain.com/userfiles/files/43278570356.pdfIn PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/kinilavagupafob.pdfIn PDF document text
    • http://brava-ekb.ru/userfiles/file/94243836384.pdfIn PDF document text
    • http://iphonedown.com/ckfinder/userfiles/files/xafubesuxefof.pdfIn PDF document text
    • http://heibldr.hu/FCKfeltoltott/file/wobideku.pdfIn PDF document text
    • http://digitalpolicycouncil.com/imagenes/file/zubobuwotirefoji.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/27925806063.pdfIn PDF document text
    • https://mepho.hu/ckfinder/userfiles/files/kuruzawepebuz.pdfIn PDF document text
    • https://pt2-turbo-j3t.com/contents/files/80296623412.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/nogebipobog.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/92236880081.pdfIn PDF document text
    • http://artgrafika.cz/userfiles/file/30423717896.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/16140815725407---solorunusiv.pdfIn PDF document text
    • http://synhbio.com/upload/files/73673300823.pdfIn PDF document text
    • https://gberwanda.com/gbe/useruploads/blogs/files/pogilenujizazanurojuzu.pdfIn PDF document text
    • http://pinedafoundation.org/imageuploads/file/59993527132.pdfIn PDF document text
    • https://bdprescription.com/ci/userfiles/files/xefusumufubafebilepa.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/37762026627.pdfIn PDF document text
    • https://hyundainhapkhau.vn/upload/files/jipafewobabokewipojomare.pdfIn PDF document text
    • http://www.programasaudetotal.com/arquivos/file/loxafinapipipamudikot.pdfIn PDF document text
    • http://studiospazioambiente.it/userfiles/files/xelisefarosebugu.pdfIn PDF document text
    • http://panda-es.tokyo/yamituki-n/uploads/files/19848199685.pdfIn PDF document text
    • https://www.pelicanfinancialnetwork.com/ckfinder/userfiles/files/9336687517.pdfIn PDF document text
    • http://cokhihoangvinh.com/uploads/userfiles/file/satipakubaweka.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_off0000e711.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE711 22420 bytes
SHA-256: 0180ddc6ed9800bcff2a632e1ea6fb96a5ca6292cc444bf3170d5d208b98ff7f
font_01_sfnt_off00012194.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12194 10432 bytes
SHA-256: f7ed90209a8f70a6733eee602ac303e33e46009c92729d6733b13b425bdfbeea
font_02_sfnt_off00013958.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13958 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1