Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd8ac99098732b55…

MALICIOUS

PDF

97.1 KB Created: 2021-07-06 14:17:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 0284ce9de585e1f64e0569f717ed256a SHA-1: 0f187332fe31d849c6b446d4a8aa0c0f7788d4b8 SHA-256: cd8ac99098732b555403077831ade3b2b642846400d5b6974b2e0d82bf793b16
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, likely to redirect users to malicious sites. The document body is unreadable, but the presence of many external URIs and the overall structure strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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 https://vietfun.com.vn/wp-content/plugins/super-forms/uploads/php/files/qe4db180g71ds3b8m09itn1ogp/43447125782.pdf In PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/2qfta2mj19gprglnuhbfitqoqn/86792095633.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608ff507191c4---96872249772.pdfIn PDF document text
    • https://www.blackandwhite-salon.com/wp-content/plugins/super-forms/uploads/php/files/1aa31ed964831d03febc998f0a33bcfa/jezajogugesananuzubipone.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/79318503116.pdfIn PDF document text
    • http://afghansolar.com/userfiles/file/zukado.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/160bdafc009311---gilizeguxanabarajoguvub.pdfIn PDF document text
    • https://photojet.bg/userfiles/file/79863223770.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210630003403.pdfIn PDF document text
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/66264e575cdb79fa5aab8d9330fca176/87555357782.pdfIn PDF document text
    • https://dtcprojects.com.au/wp-content/plugins/super-forms/uploads/php/files/ue8abmbbmiarbgu9ib1iuq9oqs/nofekesopulixesoj.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1608bc7ec1ca34---4571575426.pdfIn PDF document text
    • https://anfauglir.com/images/file/sudunilitip.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/otp13d5v6c5dpknoh2o31cru35/89408393119.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/ptb6b1i17tob22m2als78ifgcl/47569424677.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/2f1e28a745ca90a2df20f259755d2b48/suwujosuvigodidisesuza.pdfIn PDF document text
    • http://askort.pl/Upload/file/45974968477.pdfIn PDF document text
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a947596c78f---20663562473.pdfIn PDF document text
    • https://rajaketiga.com/contents//files/potapidozamosilorap.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/c4df25c05bb8d95dea95044e298e0e28/69991208976.pdfIn PDF document text
    • https://terravistahometeam.com/wp-content/plugins/super-forms/uploads/php/files/147d673ad85e7fb157a43e4426abea0f/xurelunudewiwudabale.pdfIn PDF document text
    • https://idfusionllc.com/wp-content/plugins/super-forms/uploads/php/files/815ee8a62c758f47d0060cebf96dd804/jokogizobujazodefozir.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/pemuv.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/16072ad4baa1f2---51717438246.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8c28520b0---85570918428.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=classic+wow+rogue+guidePDF 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_off000116b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116B4 10560 bytes
SHA-256: bf1fd82243dad0a9009fe559eb0be7d31ef2f55568a54a8215f956fbf397e0a2
font_01_sfnt_off00012ec9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EC9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000146db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146DB 18232 bytes
SHA-256: 519b11005e397edc2cdd26e867db24dbe44bb5cdcde63232543381f43abd2477