Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff248b9d27920570…

MALICIOUS

PDF

86.9 KB Created: 2021-09-18 00:42:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0a9a9406b0238a463025d91708919c9d SHA-1: 074e49aaf939a7bbc8a5acd2cbac6453aeebd90f SHA-256: ff248b9d27920570f1ad966a80e343891d3d2fa5271e3464a36f2ffe3dddbc28
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as a phishing trojan and ML classifiers indicated a high probability of maliciousness. Heuristics reveal multiple external URIs, including one pointing to a raw IP address and others hosted on compromised WordPress sites, suggesting a link farm designed for SEO poisoning. The document body is heavily obfuscated, preventing analysis of its direct content, but the presence of numerous links to potentially malicious PDF files indicates a clear intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • 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://krisoc.ru/uplcv?utm_term=top+android+games+2015+offline PDF link annotation
    • http://sweepinstyle.com/userfiles/file/15616820873.pdfIn PDF document text
    • https://koncnc.com/genelresimler/file/3363401643.pdfIn PDF document text
    • http://hotelniagararimini.eu/userfiles/files/96575318097.pdfIn PDF document text
    • http://phongthuyphatloc.com/luutru/files/xivixejibinajilezidis.pdfIn PDF document text
    • http://www.stallionreadymix.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16137d2102d74a---zituzidopifeta.pdfIn PDF document text
    • http://specialcats.nl/media/files/786268212.pdfIn PDF document text
    • http://rhondachem.com/d/files/23749507566.pdfIn PDF document text
    • https://fong-cai.com/upload/files/migudixijakusa.pdfIn PDF document text
    • https://webmenuplus.com/images/file/38677127809.pdfIn PDF document text
    • http://megatex-plast.ru/pub/file/pomezaz.pdfIn PDF document text
    • http://th-hl.com///upload/files/5150065541.pdfIn PDF document text
    • http://hoadon-dientu.net/images/files/kedaw.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/161370014adccd---48173038491.pdfIn PDF document text
    • http://les-dvorik.ru/userfiles/file/55339846403.pdfIn PDF document text
    • http://africareview.in/userfiles/file/xefupu.pdfIn PDF document text
    • http://panhongbo.com/ckfinder/userfiles/site_eachfun_com/files/23634323245.pdfIn PDF document text
    • https://selispin.com/calisma2/files/uploads/kifulotipewog.pdfIn PDF document text
    • http://www.iciparis.ru/ckfinder/userfiles/files/jekogiputadafebofovosi.pdfIn PDF document text
    • http://stavclearing.ru/upload/files/84116891144.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/27645747575.pdfIn PDF document text
    • http://sztarmedia.hu/_user/file/86163486789.pdfIn PDF document text
    • http://185.33.116.145/~acus01/upload/files/fawuguworupolerexavasoful.pdfPDF link annotation
    • https://stpeterscbs.ca/ckfinder/userfiles/files/26664645729.pdfIn PDF document text
    • https://mosoptagro.ru/wp-content/plugins/super-forms/uploads/php/files/fff566e9a0ebce4796161cd5909b6607/40510696476.pdfIn PDF document text
    • https://mclandpin.com/calisma2/files/uploads/73065080668.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_off0000f021.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF021 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010833.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10833 16752 bytes
SHA-256: 8da9213046ad3094630f10887303581faab58ac09b45780ed5578ae4da0fa447
font_02_sfnt_off00013388.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13388 11136 bytes
SHA-256: 01a7a529d6d390caa19f5b47b19d774f01fd6151ba2997920bb2217c4d801654