Malicious PDF — malware analysis report

Static analysis result for SHA-256 f0a8cc8613ceac1d…

MALICIOUS

PDF

83.0 KB Created: 2021-09-18 17:18:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 84aa98e8fb5998a1bd0521e7552e0262 SHA-1: 4ef1870225aa179581a3db36d311f2b246d25650 SHA-256: f0a8cc8613ceac1dac9135e259f37b9f7ca9efc304990b4e1d3addae690ff315
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of links pointing to compromised CMS uploads and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. Although no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is intended to redirect users to malicious sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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
  • 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 https://master.plus/wp-content/plugins/super-forms/uploads/php/files/763ba099b8ab48e631b26d1e4cbb729f/24357681836.pdf In PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613ed3de4ff01---70440772446.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/75664508005.pdfIn PDF document text
    • http://travelport.pl/userfiles/file/gidebivimukupawo.pdfIn PDF document text
    • http://gorsilawfirm.com/userfiles/file/25923999751.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/kmi1eq2ucei7s7ka8hpp2214da/53641596897.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/xoxomarowulurapadexarar.pdfIn PDF document text
    • https://smoothnomad.com/wp-content/plugins/super-forms/uploads/php/files/mg2jqu038sgaookmnodu7pb0fc/21570183121.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/udg07kc3oa96nqs52dsftbvo1j/wuwozaro.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd1c76c1d0---refanifasojititafugis.pdfIn PDF document text
    • https://www.wappa.com.au/siteadmin/ckfinder/userfiles/files/sewaw.pdfIn PDF document text
    • http://www.tsahimmongol.com/uploads/images/files/xanexadasudorawikajut.pdfIn PDF document text
    • http://music-saikung.com/ckfinder/userfiles/files/97345797210.pdfIn PDF document text
    • http://autobedrijvenindex.nl/images/uploads/29556507849.pdfIn PDF document text
    • https://habibitours.org/ckfinder/userfiles/files/13981806398.pdfIn PDF document text
    • http://moyamoya.center/images/hand_uploaded/files/26582627304.pdfIn PDF document text
    • http://stylowa-pss.pl/userfiles/file/linupeginirenusagiz.pdfIn PDF document text
    • http://novastal.pl/userfiles/file/maponi.pdfIn PDF document text
    • http://jinshi66.com/uploadfiles/files/xakadopupel.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/lulinimudodubeposulebofe.pdfIn PDF document text
    • https://sibconsulting.com/contents/files/14683539495.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/32795774795.pdfIn PDF document text
    • http://budgettranslation.hu/sites/default/files/file/34428404973.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/userfiles/file/jafixapetovukike.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=wonder+woman+2020+full+movie+downloadPDF 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_off0000ddae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDAE 18352 bytes
SHA-256: 889f445166392e95a449077d433df2104c1a41c656e13fb5bde7a76bbc3b5900
font_01_sfnt_off00010d41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12558 10736 bytes
SHA-256: 50d355c7981100a2561065793b4209c94a845be53cd7099ed58aa4a82cced8db