Malicious PDF — malware analysis report

Static analysis result for SHA-256 50551db40d5dd9af…

MALICIOUS

PDF

82.2 KB Created: 2021-09-23 04:50:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: be9775953b8f3867f2f7bb12db997f2d SHA-1: b56dec9860392d8496406ffda9482a7bd4228309 SHA-256: 50551db40d5dd9afa5abe4a979269dbccd4250d62f1b815ac613c50013f06655
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting, suggesting an attempt to distribute phishing content or malware. The presence of external URI heuristics and link farm indicators further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://89928386.com/uploads/files/202109040527399999.pdf In PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16130f6163f800---4523378729.pdfIn PDF document text
    • http://hocikto.info/userfiles/file/77827952446.pdfIn PDF document text
    • https://www.wemservice.com/ckfinder/userfiles/files/gogenodavuwidusi.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/16139053caee7f---14174825541.pdfIn PDF document text
    • http://www.espaciocultivarte.com/ckfinder/userfiles/files/83219718838.pdfIn PDF document text
    • http://www.donboscovizag.org/images/files/borekemapal.pdfIn PDF document text
    • https://davidfoleyinc.com/userfiles/file/baroxesovop.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/46899412531.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/tilikuvojapubeloj.pdfIn PDF document text
    • http://ashokarefrigeration.com/userfiles/file/tosutebonokuxalixi.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcead0ef01---sosupejat.pdfIn PDF document text
    • https://foulardfotografando.it/file/78464199085.pdfIn PDF document text
    • https://vcubusinesssolutions.com/userfiles/file/noruzokekasox.pdfIn PDF document text
    • http://debandhelder.nl/ckfinder/userfiles/files/63499288479.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16139b185447d9---tojuruliniruzaxivemiridef.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/16149d65adfd32---vixoxegupezafufito.pdfIn PDF document text
    • http://chataphan.com/file_media/file_image/file/guteludesifoji.pdfIn PDF document text
    • http://www.gesas.it/media/mailinglist/file/74069494823.pdfIn PDF document text
    • https://houstoncoinclub.org/FCKeditor/file/pofumumuxibo.pdfIn PDF document text
    • http://www.painters-restaurant.com/userfiles/file/91391508831.pdfIn PDF document text
    • http://kfbma.org/files/fck/file/bifuvotekasidukubudar.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/vuligerasakoribibogefon.pdfIn PDF document text
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/95776439023.pdfIn PDF document text
    • https://g4m3s-4p1-12s1.com/contents/files/34004157947.pdfIn PDF document text
    • https://bipalisdemo.dashindonesia.com/userfiles/files/29097243715.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=virtual+dj+para+android+fullPDF 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_off0000dbd0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBD0 18300 bytes
SHA-256: 0a71c1dc00bb6cb44807a8da640490e64f856e90f9f916cfe33ac84e25313ae6
font_01_sfnt_off00010b1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012335.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12335 10388 bytes
SHA-256: c753db394369629262ebf72461c9cf7d2dd44d96b3f82f7d26129fe4bcda7bd1