Malicious PDF — malware analysis report

Static analysis result for SHA-256 df5a421bf513335e…

MALICIOUS

PDF

107.8 KB Created: 2021-09-09 18:33:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 30a301c001ec7a30f1c738403336999d SHA-1: 237efa3ada4c7130a3bf0877b07da11df2a25f41 SHA-256: df5a421bf513335ef80afef544c41ce96e7bb3047a25c4ed476a41ebfb22bd35
156 Risk Score

Malware Insights

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

The PDF was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing or trojan variant. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9967

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://radiosmile.hu/upload/file/fufanozijumepuvav.pdf In PDF document text
    • https://robertmatzuzi-massagetherapist.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16139c6686d87e---74852119503.pdfIn PDF document text
    • http://infinity-c-t.com/userfiles/file/50593840524.pdfIn PDF document text
    • https://hbfilm.ca/resimler/files/sirapivuka.pdfIn PDF document text
    • https://visualarchive.bg/files/rozurakuvivovepuxux.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/enls877gs31l6hd7gs04jsggrf/2422394836.pdfIn PDF document text
    • https://quanghuydulich.vn/img_duhoc/files/44934567478.pdfIn PDF document text
    • https://miguktour.com/FileData/ckfinder/files/20210909_4DB32EAADA7652F3.pdfIn PDF document text
    • http://dj-maily.com/uploads/pages/files/36005159778.pdfIn PDF document text
    • http://zjnep.com/ckeditor/ckfinder/userfiles/files/kevimowi.pdfIn PDF document text
    • http://ekbdrive.ru/ckfinder/userfiles/files/51204990410.pdfIn PDF document text
    • http://shiraz.sk/ckfinder/userfiles/files/93466567716.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139ff460efe4---geguti.pdfIn PDF document text
    • http://retrolondontees.com/userfiles/file/94272375552.pdfIn PDF document text
    • http://tilestone-pools.com/i/File/joludabanirenofoli.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///202109025852_967840961.pdfIn PDF document text
    • http://baltyk.recykling-rejs.pl/imgturysta/files/pibibaxonififatem.pdfIn PDF document text
    • http://rorolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nuvovijatelodexalebolerox.pdfIn PDF document text
    • http://clean-ecology.com/Upload/files/79560744150.pdfIn PDF document text
    • https://dienhoanghean.com/upload/ck/files/50979675545.pdfIn PDF document text
    • http://www.americaninvest.net/upls/files/30034814842.pdfIn PDF document text
    • https://thaiahpa.com/flash/files/72642000990.pdfIn PDF document text
    • http://schokozentrale.de/idata/87538759849.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/zokinalabiselironuli.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=atlas+de+los+pueblos+indigenas+de+mexico+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_off00013987.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13987 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001519e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1519E 11188 bytes
SHA-256: 8b918054ed01efb30c203be5dedd01df496ac8129176212c9beb3c56ea117498
font_02_sfnt_off00016b62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16B62 21016 bytes
SHA-256: 7906fd451800a20f433d6c1d63043e53c1a9e971efff64bc9651d0822cf90e00