Malicious PDF — malware analysis report

Static analysis result for SHA-256 91cb4859e767333d…

MALICIOUS

PDF

81.6 KB Created: 2021-09-16 23:29:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2d739d91717513f2649a067cbb7e58e5 SHA-1: 6c96974f76d6f1a17f63a64d7eadef709372b947 SHA-256: 91cb4859e767333d4b74e216cb1a96d1b96e9b322a13aaf316b032e93ffe6c17
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of link farms on disposable hosting, and some directly point to IP addresses. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to redirect users to malicious sites, potentially for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9797

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://cructi.ru/uplcv?utm_term=fx+master+pro+mod+apk PDF link annotation
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/161311fd2d040d---kulimumofix.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/dojemejav.pdfIn PDF document text
    • https://gretajensen.com/ckfinder/userfiles/files/vedud.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/lipurulazukej.pdfIn PDF document text
    • https://coolingrealestate.com/your-home-cleaner/FCKuploads/file/goganebaf.pdfIn PDF document text
    • https://www.kuwaitpolyurethane.com/ckfinder/userfiles/files/77871098993.pdfIn PDF document text
    • http://hizirferforje.com/admin/fckeditor/editor/images/file/88508840290.pdfIn PDF document text
    • https://pushtypathshala.com/demo/aims/files/images/files/bajezadekitajokamipo.pdfIn PDF document text
    • https://taiwancy.com/app/webroot/userfiles/files/luneru.pdfIn PDF document text
    • http://metamorfoza-krosno.pl/userfiles/file/83739367408.pdfIn PDF document text
    • https://wtmasonry.com/ckfinder/userfiles/files/rovawuvubipivutafiluj.pdfIn PDF document text
    • http://challendor.com/fckeditor/upload/file/6010167620.pdfIn PDF document text
    • http://exosportsante.fr/ckfinder/userfiles/files/22003069821.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614014c2f3d4a---sereginusipof.pdfIn PDF document text
    • https://hearing-outlet.com/uploads/files/202109051417345230.pdfIn PDF document text
    • http://dongphat.net/upload/files/xasogevizegopuxisovase.pdfIn PDF document text
    • http://dui-antidote.com/images/userfiles/file/30275033152.pdfIn PDF document text
    • http://lesbambousbleus.fr/ckeditor/upload/files/judeduzomoxijapano.pdfIn PDF document text
    • http://bukharaatlanta.com/sites/default/files/file/50709022945.pdfIn PDF document text
    • https://lecourbe.dk/userfiles/file/51235767559.pdfIn PDF document text
    • http://aunay-sous-auneau.fr/ckfinder/userfiles/files/vopupakudo.pdfIn PDF document text
    • http://smcertificationservices.com/userfiles/files/pululomodaponuwawu.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/10367994897.pdfIn PDF document text
    • https://telechips.com/ckfinder/userfiles/files/vaxejejexidutoramatuwupul.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/75616548444.pdfIn PDF document text
    • http://211.129.1.225/system/ckfinder/userfiles/files/43386094001.pdfPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c4dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4DC 10484 bytes
SHA-256: 84eccb958b9b7d1da2e31c052ac30ed7856bd0e2848e396cae3a017e2ecd6db3
font_01_sfnt_off0000dcb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f4c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C7 16880 bytes
SHA-256: bbd894c524ac92b5db75558e15e35ea47541beee2589f9a75784604523a523ce
font_03_sfnt_off0001202e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1202E 16448 bytes
SHA-256: 0e4cde3d5bdd5452960de995a4807c8da4ec665155a9812e2f8e54e6c49b7878