Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d317940e2499e58…

MALICIOUS

PDF

79.6 KB Created: 2021-09-05 09:02:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 23a31633b8e4bbb9a74237af74ada17c SHA-1: 583b21700e7025f5b28d8b146e7d276830ae43f3 SHA-256: 5d317940e2499e58e879cff7715ee11bdaf7257b02e4e99722377b2bf7ca931c
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URLs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall structure indicate an attempt to lure victims to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://krisoc.ru/uplcv?utm_term=english+file+advanced+teacher%27s+book+pdf+third+edition PDF link annotation
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/a8a898e22db242581c4b66ca025aeb20/15414065972.pdfIn PDF document text
    • https://egokituz.org/files/galeria/files/wakivepofamimekodizuf.pdfIn PDF document text
    • https://eagle-aviation.com/userfiles/files/41999325130.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/ripemenafabalabuwepi.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a59bf90c46b---negezibu.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/jopudopi.pdfIn PDF document text
    • http://pincesorvarshop.hu/editor_up/10623480757.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/ad308c015870f925319287df5b93d6e7/tatorezukosexuzogis.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/13877434537.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608295a97d507---sibagigixometibisezefubu.pdfIn PDF document text
    • https://jamurgoreng.net/contents//files/garupolal.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dda2e0e17ed---13492218463.pdfIn PDF document text
    • https://atlasautoglass.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a90ff185b2---vezomezabuje.pdfIn PDF document text
    • https://tarzminder.com/resimler/files/fepekusiloraduzil.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/94194449197.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e3dbe2daf8b---xakamabeworojulaxaw.pdfIn PDF document text
    • http://promador.pl/userfiles/file/95114032843.pdfIn PDF document text
    • https://aletihad-group.com/userfiles/files/veleriwixojigizekese.pdfIn PDF document text
    • https://prtl.pl/userfiles/file/50664229632.pdfIn PDF document text
    • http://mineraux-et-lithotherapie.fr/ckeditor/upload/files/61625874140.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/aa70c7d8097dd75d34990e5ec5d62728/dejilej.pdfIn PDF document text
    • http://aristosaigonhotel.vn/uploads/files/20065291439.pdfIn PDF document text
    • https://tsydesign.com/userfiles/jws/files/12324165930.pdfIn PDF document text
    • https://gmonlinestore.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073686bbf135---nigutet.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/5051141687.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_off0000cad7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAD7 11216 bytes
SHA-256: 578a2409a5fd31e08334d6496c888ef36d1168dd8490ac5556b8afd3956cca76
font_01_sfnt_off0000e4a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A0 19684 bytes
SHA-256: f919a9be57ec4e7b1a52abfd294d9a30561c651137db3830f5ac3ed427842464
font_02_sfnt_off000117c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1