Malicious PDF — malware analysis report

Static analysis result for SHA-256 44f8a5289f7e5ad5…

MALICIOUS

PDF

80.2 KB Created: 2021-08-14 19:12:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 80e468c71c7a16419fa75e5014f7315a SHA-1: 54e65f2a3a5885da6e5b6270b9ef02dd178d1a07 SHA-256: 44f8a5289f7e5ad5c4313e552952d37b49222d27a04f1c3aaeeea50e3bd08104
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF document identified as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, forming a link farm. The presence of these links suggests an attempt to redirect users to malicious or phishing content, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://asiadomainstore.com/userfiles/file/5721853438.pdf In PDF document text
    • http://isystem.hu/userfiles/file/rufuvezuterulus.pdfIn PDF document text
    • http://barudan.hk/UploadFile/file/20210702040514938.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a55dc641afa---pafexo.pdfIn PDF document text
    • http://www.bash.cl/media/file/migufirebeparumusuganak.pdfIn PDF document text
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/ef527aa3cac6e2899426c572051d0a58/mekefelujujutugenozopesu.pdfIn PDF document text
    • https://syntellect.ru/Repository/file/71100487964.pdfIn PDF document text
    • http://dzwigipoznan.pl/userfiles/file/87727732016.pdfIn PDF document text
    • http://ciccioinpentola.com/userfiles/files/bewisitubawofur.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/aba6bdb10954db00a40f833785429287/81282176477.pdfIn PDF document text
    • https://cardion.dk/gfx/fckimages/file/77193007685.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/8eb2d9e65b3945f9f0275e245ff49adf/semapafojerubidesopinene.pdfIn PDF document text
    • http://studiopedrazzini.eu/userfiles/files/jaludopavetutirulokuzu.pdfIn PDF document text
    • http://scan3dsaigon.com/upload/files/99032836412.pdfIn PDF document text
    • https://nocenzura.space/web/img/podborky/files/libatujoxeson.pdfIn PDF document text
    • http://fsnmmaterials.com/UPFILE/userfiles/files/89274287751.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161159e1d8cbf4---80039920970.pdfIn PDF document text
    • https://wilsonbarrera.com/inicio/wp-content/plugins/formcraft/file-upload/server/content/files/1608355f82401b---72122435455.pdfIn PDF document text
    • https://bellevuecommunityfoodbank.org/wp-content/plugins/super-forms/uploads/php/files/2f1abda2787b5f9af3d8b66423f1bc86/gojisuxosogujamujewemib.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5cfeb71fef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=cuantas+celdas+tiene+una+hoja+de+calculo+de+excel+2016PDF 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_off0000cf44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF44 18612 bytes
SHA-256: f146fbd26bd797550848a9f48250fa724ff15a2c8d8d0d988872489ea0be6b76
font_01_sfnt_off0000ff22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF22 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011739.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11739 11192 bytes
SHA-256: 2c63626cf6d88fb76d824407a075aaaf7ed7a8876b9c808c3a1c62a5433ca3ca