Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ac81d6575bcc836…

MALICIOUS

PDF

73.2 KB Created: 2021-09-24 17:03:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e6eacc4c9cc39cbca3ef0f2c97d7a1cc SHA-1: 779d7452c5373536c343f2a2bfd4c532aca161d2 SHA-256: 5ac81d6575bcc8365ba3580c237877a68f4171d3aca9d0043b16f152de028b4b
124 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV with a 'Pdf.Phishing.Trojan' signature. Static analysis reveals it functions as a link farm, containing numerous URLs pointing to various domains, some of which are hosted on compromised WordPress sites or disposable hosting. The embedded URLs and the overall structure suggest an attempt to lure users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4113

Heuristics 5

  • 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
  • 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://cructi.ru/uplcv?utm_term=principles+and+practice+of+physics+solution+manual+pdf PDF link annotation
    • http://hak-al.com/resimler/files/24081356815.pdfIn PDF document text
    • https://kp-bs.ru/upload/files/47281703740.pdfIn PDF document text
    • http://huzatfokozo.hu/editor_up/bepejikinuperureremorido.pdfIn PDF document text
    • https://hyundainhapkhau.vn/upload/files/20365334306.pdfIn PDF document text
    • http://jarauwerdaenzn.nl/userfiles/file/20737572958.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/f70fc0bf9f8153a997680c3e14c5d974/68145107769.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/44145887507.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/96671260299.pdfIn PDF document text
    • http://bronia.org/userfiles/file/fabulo.pdfIn PDF document text
    • http://dpsszczytno.pl/photo/file/36066936481.pdfIn PDF document text
    • https://enilubricant.hoakhanh.vn/uploads/image/files/ponatejijuna.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/f561a913f5757dfbd940ac225ba6b934/dedigodedidekosu.pdfIn PDF document text
    • https://atkarisuli.hu/userfiles/file/48531815323.pdfIn PDF document text
    • http://vetportonaccio.it/userfiles/files/28471298295.pdfIn PDF document text
    • https://vzduchotechnickefiltry.cz/docs/vujeladeda.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/07e4ef4f7a0b6e58c05126913226f433/pizuwetasuzasepuvewero.pdfIn PDF document text
    • https://groupekineconcept.com/userfiles/file/9158752513.pdfIn PDF document text
    • http://www.village-gaulois.org/gestion/ckfinder/userfiles/files/91487769036.pdfIn PDF document text
    • https://silverbirdmarketing.com/pages/images/file/luvugagesawamipub.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130517451599---mofusimujomisek.pdfIn PDF document text
    • http://liavanhaeringen.nl/userfiles/files/52551373703.pdfIn PDF document text
    • http://ad.ditroinfotech.com/laportal/ckeditor-ckfinder-integration/uploads/files/74325223312.pdfIn PDF document text
    • https://bhandarisurgical.com/ckfinder/userfiles/files/jozimefepepalolij.pdfIn PDF document text
    • https://www.hotel-restaurant-plainfaing.fr/ckfinder/userfiles/files/4169294755.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ceaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEAF 20188 bytes
SHA-256: 7f7f817980a2370696766599a1d08874b4abc0d9cb2a61a72a1a38c570842098
font_01_sfnt_off00010406.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10406 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1