Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bd3cb91cf696244…

MALICIOUS

PDF

78.5 KB Created: 2021-09-14 07:53:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: ec8916052ffec5a53cb8166a7aca9138 SHA-1: ae3cf04664d5d4f7d3c15f6ec3701a18db7896f1 SHA-256: 6bd3cb91cf69624403cadf2fc72c3f29ee2efdf11e218e267f662d62c915e2e5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and link farm heuristics point towards a malicious document designed to lead users to compromised or malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://pickup-ws.com/userfiles/files/35722804770.pdf In PDF document text
    • https://alzubidi.com/userfiles/files/lupaxaxuzi.pdfIn PDF document text
    • https://limsurdua.com/contents/files/83688014853.pdfIn PDF document text
    • https://erdenetpost.mn/userfiles/files/narumaxonuwar.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130d0df733b7---79373987008.pdfIn PDF document text
    • http://luckyassessoria.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613e66f3d56ef---62078135424.pdfIn PDF document text
    • http://homestationrealty.com/userfiles/files/nuraboriti.pdfIn PDF document text
    • http://guerrazzi.info/userfiles/files/paxesabujojikala.pdfIn PDF document text
    • http://worldnaturalfood.com/image/upload/File/zemebukiluxiguxu.pdfIn PDF document text
    • http://lynxitservices.com/ckfinder/userfiles/files/53784876160.pdfIn PDF document text
    • http://spielundlicht.de/content_provider/documents/files/95898715154.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/7d037dec0a6cffac3b55f0935eba8a5a/fewitixalodi.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/57863918249.pdfIn PDF document text
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/go14scjo5h93v676e2dv37stg6/75106113200.pdfIn PDF document text
    • https://vaitinhdien.com/app/webroot/upload/files/ragasefunirumivodak.pdfIn PDF document text
    • http://portableandcool.com/files/files/xobigolutoxivufabuza.pdfIn PDF document text
    • https://falconshipping-uae.com/userfiles/files/83944074186.pdfIn PDF document text
    • http://abwlargo.com/uploads/files/bulilugiruri.pdfIn PDF document text
    • https://bartonsteel.com/tony/barton/ckfinder/userfiles/files/95611356566.pdfIn PDF document text
    • https://jpt.mysmartedu.com/uploadimages/files/69870881384.pdfIn PDF document text
    • http://xn--66-6kc8bfmkmjd.xn--p1ai/admin/ckfinder/userfiles/files/59230183905.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=resume+mail+sending+formatPDF 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_off0000d011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD011 17128 bytes
SHA-256: fb23d20e10f57d25c012189bde70e52f970604330445698281dc90c6fec2c90d
font_01_sfnt_off0000fc14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC14 10840 bytes
SHA-256: 57d570f5e4ac4cabb2a5da7174783f2e9e12a2089c5a954a0dc9c368a71113e4
font_02_sfnt_off000114e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1