Malicious PDF — malware analysis report

Static analysis result for SHA-256 31d7270bff71b09c…

MALICIOUS

PDF

82.5 KB Created: 2021-10-08 10:09:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 379d91c4148baab6031300aac13cb2f0 SHA-1: 626ac7408dc3c5f6b360f8435ee60f81005d874b SHA-256: 31d7270bff71b09cb4b0e2a63dfe21e35c4bfa5f2fed0184699fadea55582ccd
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious sites. The embedded URLs, while some are marked benign, are part of a larger pattern of potentially harmful redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/16139468ec577d---97529856960.pdf In PDF document text
    • http://qlionshousing.ca/userfiles/file/wijetegotolopomogakebaj.pdfIn PDF document text
    • http://duet-czluchow.pl/userfiles/file/19439098491.pdfIn PDF document text
    • http://terredellamagnagrecia.com/userfiles/files/bowafexaxasivenodimub.pdfIn PDF document text
    • http://kamennykoberec.eu/editor_uploads/system/files/sasatavapasunuzulutegago.pdfIn PDF document text
    • https://xn--80aaijz0c.xn--p1ai/ckfinder/userfiles/files/65843355257.pdfIn PDF document text
    • https://stancijanegrin.com/UserFiles/files/67533830012.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/b42e938225557009d925c838dc9b1039/gevifobemuxugewefa.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/6281934274.pdfIn PDF document text
    • https://krygina40.ru/UserFiles/File/95103720094.pdfIn PDF document text
    • http://hbaoge.com/upload/files/52285105733.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/1614020c1436de---dafaligonurofileb.pdfIn PDF document text
    • http://npcbalkan.net/ckeditor/ckfinder/userfiles/files/4687590070.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/kuwirig.pdfIn PDF document text
    • https://verredistri.fr/xmedia/file/veguxitepotasemurenije.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/fedigizasajowa.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/1615a12ce42f85---26321908072.pdfIn PDF document text
    • http://wasserentkalkung.at/ckfinder/userfiles/files/70890526825.pdfIn PDF document text
    • https://cupanghitam.com/contents/files/xifitojugu.pdfIn PDF document text
    • http://intemhathanh.com/img_duhoc/files/26730832292.pdfIn PDF document text
    • https://alubiasdetolosa.com/files/galeria/files/lozekegagojatolixi.pdfIn PDF document text
    • http://trendstyleimage.com/uploads/ckfinder/userfiles/files/76170817994.pdfIn PDF document text
    • https://mamalight.org/business_school/uploads/file/zagituseketolod.pdfIn PDF document text
    • http://clubesquilacoma.com/uploads/files/68002254826.pdfIn PDF document text
    • http://thecargonepal.com/userfiles/file/46694603951.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=addison+and+charli+and+dixiePDF 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_off0000da44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA44 10452 bytes
SHA-256: d429598cda31cd8cfc901e3c957484a8209da28f388c3514be55b6cf5fa16174
font_01_sfnt_off0000f1ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109FC 19580 bytes
SHA-256: 2400702782696878c7e7a546acef6f9698091b4de7f59503893332c994f47390