Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a43117c1e87f75b…

MALICIOUS

PDF

74.6 KB Created: 2021-10-07 15:30:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: fed8f3c91642f510da771d08ac460e76 SHA-1: c99e7ed4c0a3214fb37ac120ca02fffa1ed976c9 SHA-256: 7a43117c1e87f75b80bee3b4f6070a58e66c83c5f4f9b568bd8064187cebad65
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload storage and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure and URL patterns are indicative of a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://infrive.ru/uplcv?utm_term=sudden+fever+and+chills PDF link annotation
    • http://bualuang101.com/backoffice/upload/files/jojumasowopa.pdfIn PDF document text
    • http://simonhoirup.dk/userfiles/file/81074206774.pdfIn PDF document text
    • https://radekslodkiewicz.pl/files/file/83025681167.pdfIn PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/dumefatopapivitogiwewufiw.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/pododobos.pdfIn PDF document text
    • http://pr-jam.com/ckfinder/userfiles/files/letasavonusixulanot.pdfIn PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/f79ad4535a8432c249b1d0df443c8602/gijudugajagofilasok.pdfIn PDF document text
    • http://erulingua.hu/uploads/content_files/files/73787983802.pdfIn PDF document text
    • http://allineers.morefriendship.com/upload/files/32344857047.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/161526a1f76fc9---51874982402.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/749eb733c0c9f12507c0a6f4359582cc/35243374695.pdfIn PDF document text
    • https://sambelteri.com/contents/files/41169691033.pdfIn PDF document text
    • https://possamaiferramenta.it/uploads/file/lumibigabu.pdfIn PDF document text
    • http://tbeaindia.com/userfiles/file/jolesiturinuf.pdfIn PDF document text
    • http://rogersdesignhouse.com/uploads/files/63674167103.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/ja5maoq8vc3lekrjnt1d8tnucn/kiforejorimenasoled.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/pvhqhdskjvu8vjbhf72ge60qqm/juwadorotisa.pdfIn PDF document text
    • http://ersenergy.com/UserFiles/file/39108487600.pdfIn PDF document text
    • https://trade.inter-ural.ru/ckfinder/userfiles/files/lobiz.pdfIn PDF document text
    • https://cardion.dk/gfx/fckimages/file/55999810634.pdfIn PDF document text
    • http://nuklearmedizin-amro.de/userfiles/file/kilefitenuduluxim.pdfIn PDF document text
    • https://o-dance.dacola.com/upload/files/dujurisabudaviwowutigadif.pdfIn PDF document text
    • https://eravikulamnationalpark.org/ckfinder/userfiles/files/35415801238.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/najewenago.pdfIn PDF document text
    • http://jan-fotografie.nl/upload/files/1564050546.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_off0000bf47.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF47 17536 bytes
SHA-256: 5d6a007228e95b748079e932180a156d1f8d852d115376f9d34b9e2909a5702d
font_01_sfnt_off0000ed07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED07 10596 bytes
SHA-256: 3af8fc455663ad558874bdf050f1498cbca3bffdb36271f63b12602da3d03b6d
font_02_sfnt_off0001052a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1