Malicious PDF — malware analysis report

Static analysis result for SHA-256 9bdc2c0a71021f82…

MALICIOUS

PDF

87.8 KB Created: 2021-09-04 16:10:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3fda0b9b260434db7dae6f9f24f9b715 SHA-1: c258f652267c3f0c5103e5dcf2168006bb81b7d2 SHA-256: 9bdc2c0a71021f82d0350a44641ea10a4309755476d22e29bb74ed9e2ba646d9
156 Risk Score

Malware Insights

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

The PDF document contains a link farm pointing to numerous compromised websites, many of which are WordPress installations. These sites host further PDF files, suggesting a chain of redirection to ultimately deliver a malicious payload. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://nomylo.ru/uplcv?utm_term=english+worksheets+for+grade+4+comprehension PDF link annotation
    • http://www.everhouse.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1607583aa39008---vasegatapifusasupugexupet.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a12c5dccc0---64670762195.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16089be42770fd---renufafefexuvi.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/39312875644.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/efdc6c832c3352ee1700477017069495/36137247461.pdfIn PDF document text
    • http://foxadv.net/file/67117902170.pdfIn PDF document text
    • https://laser123.com/geektic/files/tejuku.pdfIn PDF document text
    • http://zaintik.org/files/galeria/files/50239504149.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/jeeeek43uvmfm8a77n440lt0t7/14168632351.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/72t6fcqnvp35n900i559o7hk2n/60530819237.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/b632378a6ee644c805b9f3897094ad4e/9161900647.pdfIn PDF document text
    • http://csaladiegyteruautok.hu/userfiles/files/16026933697.pdfIn PDF document text
    • https://zazilha.com.mx/wp-content/plugins/super-forms/uploads/php/files/0733c9e097401a5eee69129eea657f28/xuradozuwozimikegorakegi.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/6087553912.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/4d5u6aki3q9tb1v5k5nao2ps9o/sovisuxos.pdfIn PDF document text
    • https://www.advids.io/wp-content/plugins/formcraft/file-upload/server/content/files/160dbfbbf03266---bajunavi.pdfIn PDF document text
    • http://www.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/160d81f60a6988---vijitezijumituxali.pdfIn PDF document text
    • http://kodemari.info/data/files/37184029319.pdfIn PDF document text
    • http://associatedreclaimed.com/userfiles/files/binapivigugazafovino.pdfIn PDF document text
    • http://taihegas.com/filespath/files/20210827004607.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2a3d178c98---sosuxezap.pdfIn PDF document text
    • https://teenvolunteerhouston.com/wp-content/plugins/super-forms/uploads/php/files/de328bb56d0f3e6034dd28bf5da7570f/1881081960.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160acdbf34d96f---2661061245.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_off0000f123.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF123 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001093a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1093A 11308 bytes
SHA-256: f724686ad6c3fa86e40c88959d7f6ac65e9543e36736fbb8d7a581ea105aa63f
font_02_sfnt_off0001237d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1237D 17956 bytes
SHA-256: 7421a4817113e47d7a874d9cd3cc49bcd039ecaed5aeef9435070c0a20e171a6