Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a4d580f8c651816…

MALICIOUS

PDF

85.6 KB Created: 2021-09-20 20:45:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 22bfe86cdc4ab5b8493cd9aa1f330fab SHA-1: cb85c9c91a926ef6f7552d0b8091b8a9af345e86 SHA-256: 8a4d580f8c651816fb1a4fdf93dc0a006ef3b4c075e1e4f0a1c0ea41e81d5c3b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links pointing to compromised websites, including WordPress upload directories, suggesting a phishing or malware distribution scheme. The document body is unreadable, but the heuristics indicate a link farm strategy to redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://gruaszarate.com/ckfinder/userfiles/files/52567585161.pdf In PDF document text
    • https://tigaintan.com/contents/files/sibilufufasatesave.pdfIn PDF document text
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/161462c7c4c22b---zovilekokojexibej.pdfIn PDF document text
    • https://malashealthcare.com/userfiles/files/92240075935.pdfIn PDF document text
    • http://meadescafe.com/userfiles/file/81714314844.pdfIn PDF document text
    • https://vgcanada.com/userfiles/file/20283141225.pdfIn PDF document text
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/vhqs0q2bbjgbejmnr0lam8ajk3/73753411535.pdfIn PDF document text
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/4218713862.pdfIn PDF document text
    • https://ijtm.in/userfiles/file/mafofabod.pdfIn PDF document text
    • https://triangle-electronics.com/assets/userfiles/file/67830982146.pdfIn PDF document text
    • http://sherwoodchambergolf.org/ckfinder/userfiles/files/37762173574.pdfIn PDF document text
    • http://bulk-supplies.com/userfiles/files/jugujagifut.pdfIn PDF document text
    • http://phayaotechno.com/UserFiles/File/jumimil.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/83497289203.pdfIn PDF document text
    • https://yingzhaoliuart.com/upload/file/87141308420.pdfIn PDF document text
    • http://studioesflores.pl/obrazy/file/lubivizalozojowifuw.pdfIn PDF document text
    • https://www.serwkom.pl/plugins/ckfinder/userfiles/files/zinozov.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/29550543279.pdfIn PDF document text
    • http://tornyanggrace.com/upload/file/zubovojiseza.pdfIn PDF document text
    • http://logenamerica.com/userfiles/file/xanijadonadurijubezi.pdfIn PDF document text
    • http://cosmoscm.com/contents/files/vuxuz.pdfIn PDF document text
    • http://miskolciharsona.hu/pictures/file/sozikuvajesepe.pdfIn PDF document text
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/48a42c26c77bb5ca5b0c4686205b8275/jonowi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=disable+home+button+android+programmaticallyPDF 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_off0000e6e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6E9 17964 bytes
SHA-256: 2a590d67dc01ff283b35f60e4da4a605509b08d881486ad4fedb59af5deee0f7
font_01_sfnt_off00011623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11623 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012e3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E3A 11316 bytes
SHA-256: d363772bb82b01d986a0f5d8ca86475cfa4904c893d6cba1844b1eab0c17a547