Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ff8fd9698627f76…

MALICIOUS

PDF

84.0 KB Created: 2021-09-05 08:01:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 3fb8f0a91c6b0f02b6fa635488ea3b98 SHA-1: 0d1fd590ceb7260d6f984609ecb820e02288662c SHA-256: 3ff8fd9698627f76d8256683bcfd0a8466d89ce8c73ddd2d5eee39e6b2243425
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites, which function as a link farm. These links are designed to redirect users to malicious content, as indicated by the 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' heuristics. The presence of a link farm suggests an attempt to obscure the ultimate destination and evade detection, likely as part of a phishing or malware distribution 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 http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a29da99ff76---vojigidasuwojuda.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082d93d36076---56769265013.pdfIn PDF document text
    • http://www.oknookna.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160b64b1255067---96155275721.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/9921bbeafb9e87de521edec602e584f8/57183348863.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/lefabumolatasofudomiv.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d3e4fd6a927---20691859227.pdfIn PDF document text
    • https://www.hmgfinance.com/ckfinder/userfiles/files/3604025319.pdfIn PDF document text
    • http://apsons.eu/files/file/93239809678.pdfIn PDF document text
    • https://cr2tek.com/userfiles/Proj_Name//files/33654553217.pdfIn PDF document text
    • http://pferdefreunde-brueckenhof.de/sites/default/files/userfiles/file/80326991926.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/6568951c53b54d5027f9404dafa68bd9/robupo.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/16118079e62a6b---26532600842.pdfIn PDF document text
    • https://sitarasign.ir/data/file/gerakowawewosepesa.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ace6fdb619b---zakijemodofujig.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202108212331129330.pdfIn PDF document text
    • http://vanlysecurity.vn/vanly/album/files/jupob.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/3f28a330fa3c9dde7228efe37149282c/41559457728.pdfIn PDF document text
    • http://wonsakai.com/uploads/files/dakitetabixovarobir.pdfIn PDF document text
    • http://neoneofytou.com/ckfinder/userfiles/files/perixakowozakezagolemojof.pdfIn PDF document text
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16077b45e46e23---69001328001.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/3900346d830b1e2309a3d805d5ebd882/12797194926.pdfIn PDF document text
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c500660ab4a---ravofuzimokomi.pdfIn PDF document text
    • http://vivaibonomo.it/userfiles/files/39097591896.pdfIn PDF document text
    • http://goldia.cz/data/file/jofupotojorekitudit.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/874943db43274210df9425f2d44b5ef0/xijavazubawukinutaga.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=administracion+de+empresas+concepto+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE081 19076 bytes
SHA-256: 809dc6201f6f178d691db5fa0baa233cb1d13f34e1be851267e8cd6fba405887
font_01_sfnt_off0001113e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1113E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012955.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12955 10716 bytes
SHA-256: ef932d144e5290cebba7aa4d0f7b64254468c93a8611314854bf4cdb1bfbec14