Malicious PDF — malware analysis report

Static analysis result for SHA-256 39d079274a347b5c…

MALICIOUS

PDF

80.7 KB Created: 2021-08-17 23:21:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 635131beb1ef9c41dd8b4001243f10c9 SHA-1: 0e9bec8d1aea4c20fa4d9ef304e41c240cc58943 SHA-256: 39d079274a347b5caef868ddcf4bc146dfb43f9bf898a1197c25d3bcd251f026
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with several heuristics indicating it functions as a link farm hosted on potentially compromised or disposable domains. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution via these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/7e2a35ef6c02e6508fa70f41e69a17b9/niwimatudoxa.pdf
    • https://holocaustresearch.pl/nowy/photo/file/komazugisuwonokafebavof.pdf
    • http://susanirvine.com/clients/82887/File/pujofetorunadejilisufale.pdf
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/g3mrmo57d8mojsssdtconq30f3/60454407702.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16080ba3f7e234---46632080525.pdf
    • http://theemasternetworker.com/ckfinder/userfiles/files/49120202323.pdf
    • http://albino-pitti.com/pub_img/file/kesujawol.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/787cf8hngvqv7tckf4u1v2jij1/jesofuwa.pdf
    • http://s8radziejowice-paszkow.pl/userfiles/file/81189258833.pdf
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/160c08ced9b85e---mavugedixazulinovog.pdf
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b17d475a661---31108923912.pdf
    • http://centralcogtc.com/uploads/file/24704471327.pdf
    • http://myboydfamily.com/clients/7/7f/7f513a2250c12de81a70a6735749c289/File/serinovubizatipaxok.pdf
    • https://adbetelparaguay.com/wp-content/plugins/super-forms/uploads/php/files/86de2ee240f8075fa1334b7579ba7858/38598531391.pdf
    • http://gsmontaggi.it/userfiles/files/paxavef.pdf
    • http://maradonasalud.com.ar/ckeditor/ckfinder/userfiles/files/31193613380.pdf
    • https://1877painters.com/FCKeditor/file/zotemujonumobidemufokuniz.pdf
    • http://maxgear.cz/webpagebuilder/ckfinder/userfiles/files/dulus.pdf
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/c6v7tfpml72a136nnq682pr557/femijeseluzo.pdf
    • http://aceonlinementors.com/userfiles/file/kusupifugeginasidizomebar.pdf
    • https://aglogistics-bo.net/userfiles/file/nibojusi.pdf
    • http://mofrantech.com/userfiles/file/50030133770.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=holt+handbook+introductory+course+answer+key+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_off0000d4f3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4F3 16792 bytes
font_01_sfnt_off0000ed05.bin
cc4c7aaa901c669d17bd8f0b00ef1aafed297985a9523f2e0d42a15b5b0b0fe1
pdf-font-stream PDF embedded font (sfnt) at offset 0xED05 17104 bytes
font_02_sfnt_off00011a1f.bin
b55817837367990ca18a0a6ac40d5ad3d536dfcda8c5390eb733970ca21c4a2c
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A1F 11240 bytes