Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c390b6d132e507e…

MALICIOUS

PDF

69.9 KB Created: 2021-09-26 03:44:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4c020a4c88647e3c311700069346865d SHA-1: 41ba21214e1454e75dc3132fc09653cb952c2923 SHA-256: 3c390b6d132e507e7f6696a02e4a802d6e12e7865b28b109c365a90170515f6e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to other PDF files, indicating a link farm or content distribution network. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://i-try.tw/upfile/files/2021/09/16/rolazugemomidizuwuvogipum.pdf In PDF document text
    • http://ambvetesopo.eu/userfiles/files/nafagomiwojila.pdfIn PDF document text
    • https://lifeteacher.tw/uploads/files/202109230323258212.pdfIn PDF document text
    • https://mimzyonline.com/userfiles/file/52879715256.pdfIn PDF document text
    • http://kronospan-mofa.hu/editor_up/vofurikezakurejebamut.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/20219171336182899.pdfIn PDF document text
    • https://qwert5.com/psum/admin/userfiles/file/nokav.pdfIn PDF document text
    • http://www.impactit.in/ckfinder/userfiles/files/tasarodabadipit.pdfIn PDF document text
    • https://aarhuskortet.dk/images/file/19651146557.pdfIn PDF document text
    • http://mizuho-co.net/file/ck/files/36661676434.pdfIn PDF document text
    • http://9jamail.com/FCKeditor/editor/filemanager/connectors/userfiles/file/sanubamewuzezot.pdfIn PDF document text
    • http://pixel-pro.ru/upload/file/fejoridixedevavofukusix.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614c705f98a11---pavaben.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/wawolizubujize.pdfIn PDF document text
    • http://corse.annuaire-regional.com/ckfinder/userfiles/files/getajolidobuj.pdfIn PDF document text
    • https://mrpressconsulting.com/UserFiles/file/94537663603.pdfIn PDF document text
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/tl5hrif622b5jvdlul3giuet5q/36400829853.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/sovapejozedojudafutuxugin.pdfIn PDF document text
    • http://lsneotek.com/ckupload/files/junulad.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/rotatuwulifa.pdfIn PDF document text
    • https://afgventuregroup.com/cfiles/file/96091125530.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210925_A7E35F306BE6DC3E.pdfIn PDF document text
    • http://pactolous.hu/upload/file/pikevido.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=cheat+lord+mobile+2020PDF 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_off0000aea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAEA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c6bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6BC 10656 bytes
SHA-256: 6a4e7dff67fffdef098fbd2970defcb62cc4f9b2b607fe373836340d91632420
font_02_sfnt_off0000df21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF21 17384 bytes
SHA-256: 34408a8c5c2e04a99f568998904479c23739045087daeed389876a7887a4b5da