Malicious PDF — malware analysis report

Static analysis result for SHA-256 454a31ee841cd635…

MALICIOUS

PDF

80.5 KB Created: 2021-09-04 11:08:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 1db5db746589b6c2adbf8bd22956e1b2 SHA-1: 113519ba782006a2885daa411fb500346a5c3d8d SHA-256: 454a31ee841cd63512d0adc99c3654aa31aec1e97fda4ac8b389c8b8232131bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to various external URLs, some hosted on compromised CMS uploads or disposable domains. These links likely lead to phishing pages or further malware downloads, consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://archism.ru/uplcv?utm_term=mcqs+on+water+and+electrolyte+balance+pdf PDF link annotation
    • https://dondepodemosir.com/userfiles/file/25257836311.pdfIn PDF document text
    • http://sendedianqi.com/upload_fck/file/2021-7-21/20210721140736713353.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/11356866352.pdfIn PDF document text
    • http://szolnokepul.hu/userfiles/file/tataxosemalo.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/df38c3938be36f0af9ca2b4ce4f71840/walatudefu.pdfIn PDF document text
    • http://smeclassof1987reunion.com/clients/37165/File/lenizobogezejaweribimajiz.pdfIn PDF document text
    • http://tamker.hu/userfiles/file/74196356474.pdfIn PDF document text
    • http://ykzn8.com/upfiles/editor/files/kogidawize.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609785c545f6c---tubel.pdfIn PDF document text
    • http://goreskyreunion.com/clients/b/ba/ba087d28c24afe6c5bc45fa062332e47/File/49380660284.pdfIn PDF document text
    • https://q-web.ro/wp-content/plugins/super-forms/uploads/php/files/nfvo65gtcavjtikrrorna1baoi/12830947885.pdfIn PDF document text
    • https://digireg.dk/upload/lifuja.pdfIn PDF document text
    • http://ankamet.com/userfiles/file/46959766059.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/8390444305.pdfIn PDF document text
    • http://farmina.ru/uploads/files/wasobalazika.pdfIn PDF document text
    • https://mimpi1pusat.com/contents//files/63873564969.pdfIn PDF document text
    • https://unitedfightalliance.com/ckfinder/userfiles/files/sipagifowo.pdfIn PDF document text
    • http://unesco-mediain.cz/fckfiles/file/93055703938.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf983c598d0---wivafugixosu.pdfIn PDF document text
    • https://renebeumer.nl/userfiles/file/34119370548.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f7af1f0b36---66733238633.pdfIn PDF document text
    • http://griswoldremgmt.com/uploads/files/5180099256.pdfIn PDF document text
    • https://inverpalmas.com/aym_image/files/35564302218.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_off0000d505.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD505 17456 bytes
SHA-256: 90454fcebf9f0a60e61db6854156b35400cdc0dd9ce86ae6b4f1e2a7c74e6868
font_01_sfnt_off00010258.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10258 11000 bytes
SHA-256: 9227b383a2525a66934e03867ba87e3975db0597041a1308fa174d033e977721
font_02_sfnt_off00011bbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1