Malicious PDF — malware analysis report

Static analysis result for SHA-256 62f908cf23c6dec9…

MALICIOUS

PDF

86.9 KB Created: 2021-08-12 14:10:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c1ba25e2f84127fc7640de5f4559104f SHA-1: 51f444b63e5cc3a752e8010534f7ecdf0b6f7af2 SHA-256: 62f908cf23c6dec9663aaf73a6cd667de8f56c7f27c15822272afe19d766c5aa
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farms pointing to compromised CMS uploads and disposable hosting, indicating a phishing or malware distribution attempt. ClamAV detected this file as Pdf.Phishing.Trojan, and an ML classifier also flagged it as malicious. The document body is heavily obfuscated and unreadable, but the heuristics strongly suggest a malicious intent to redirect users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://drafthe.ru/uplcv?utm_term=how+do+you+write+a+daily+activity+report
    • http://sea-cruise.ru/ckfinder/userfiles/files/niwuvozibor.pdf
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16083a9c4cffd2---40351291366.pdf
    • http://americansemitruckparts.com/d/files/dutojavagomu.pdf
    • https://proxus.nl/file/jozusajikajeb.pdf
    • http://esipro.fr/userfiles/file/pisomedekawedewipi.pdf
    • http://kino-cosmic.ru/sadm_files/nudufigemagavekarugijuwa.pdf
    • http://caryhigh1987.com/clients/41333/File/41973097356.pdf
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/1611033977fab1---gikovajimetutewal.pdf
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/1a06632a306402b6dcb9491a44fec3c0/80288628069.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/f64e46d8abbbedba596fa4669973b9c3/jebogigidufimiganal.pdf
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/0b9aeccaae06e95aa53373dc3eb6c069/wulivufovumigalukotag.pdf
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b88690e9f62---11846831085.pdf
    • https://worldkelo.com/wp-content/plugins/super-forms/uploads/php/files/531fc0ce1227767490c0b2718ee38269/23130407195.pdf
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/d1b7b2d1ea8add648f36b69221bf4856/49375946907.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/f793684ae9383512043a2807cd850f73/wemarenol.pdf
    • https://seedomoretravel.com/files/files/13930535751.pdf
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095454fb0177---96528668733.pdf
    • http://greatnice.club/updatefiles/file/42395070640.pdf
    • http://huyminhplastic.com/upload/files/58494076772.pdf
    • http://konemara.hu/userfiles/file/35954446151.pdf
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/k0vdc5hnsvrjrki04g5n8h27c1/fosevapow.pdf
    • http://santabruna.cl/upload/file/merozinexopat.pdf
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608bbdbc78471---bijulipolitanav.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f28b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF28B 16792 bytes
font_01_sfnt_off00010aa2.bin
7e4a17c41dff5268518306b48fe34d2ca8a9a19a8900f11ad7eb40969f2b0e09
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA2 10592 bytes
font_02_sfnt_off000122f3.bin
626d3fc887fb055a17adc7b18a3068db936529345dc492e72a6378b4ab613a16
pdf-font-stream PDF embedded font (sfnt) at offset 0x122F3 16536 bytes