Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb55c921dea4270a…

MALICIOUS

PDF

98.3 KB Created: 2021-09-07 18:23:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 42b397a40b8eeb980a4e98634f89b0c4 SHA-1: 3b6c21e1d7f8b8fea0c972c339bd684f66e03524 SHA-256: bb55c921dea4270a8a3d0234b908785ef89e347860340b6252b068153306e5bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links, many pointing to compromised WordPress uploads and disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://huntic.ru/uplcv?utm_term=basic+human+pathology+pdf PDF link annotation
    • http://93564497.com/userfiles/90422896286.pdfIn PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/35f658bf5204a714841a8d43fad744e4/wifot.pdfIn PDF document text
    • http://annamsaigonlaw.com/upload/files/rewopikuruzinesatajubi.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/sfo929n5j3d4t14k9oe0dpkte4/95003360744.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160984587557f5---taferitisezudabu.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16071e90217f0d---pizegawolofumu.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a44d9352e02---35371559603.pdfIn PDF document text
    • https://rodolphe-blanchet.fr/Rodolphe/fckeditor/file/63811541166.pdfIn PDF document text
    • http://fabiocaronearchitetto.com/userfiles/files/1579091252.pdfIn PDF document text
    • http://runningrhinelanderrabbitry.com/clients/875187/File/nasane.pdfIn PDF document text
    • https://matfreklam.com/calisma2/files/uploads/vifemut.pdfIn PDF document text
    • http://beateromer.com/bilder/file/zatid.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/70030050394.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/1k01o9qcn393nc42o1o1hrpf76/87295081644.pdfIn PDF document text
    • https://immo-cjeanpaul.lu/userfiles/files/salutuzijigobamevus.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/49594718700.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/m4b1t74nb7qi0rsoid1c4hn0jb/miwotojubovufazokegafuxi.pdfIn PDF document text
    • http://short-story.ru/upload/file/87965613286.pdfIn PDF document text
    • http://getem.plfiles/file/xirini.pdfIn PDF document text
    • http://rauvuonsach.com/images/uploads/files/97783125280.pdfIn PDF document text
    • http://www.abcklima.hu//data/editorfile/57360732112.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/92526034572.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/mbia2hgo01n8nqos8kunssaips/xevoxelitizakuge.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_off00011a4c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A4C 11100 bytes
SHA-256: cff0812d6ab796b177e7bea12d3d4b7a65fd7ecd39576f72c9e42ebea6f5e6a6
font_01_sfnt_off000133e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133E2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014bf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14BF4 18324 bytes
SHA-256: 4be0539110cf21d08b157e283f4ffeaed1830ccc8306b0c98dbdfe07300979f8