Malicious PDF — malware analysis report

Static analysis result for SHA-256 31bd1c98e187e7b5…

MALICIOUS

PDF

79.2 KB Created: 2021-08-27 10:54:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 07196973b95ea4e51fd69fb4b9eb6be3 SHA-1: 928566ecb5973ede76f462284dc8df0e64911965 SHA-256: 31bd1c98e187e7b5a3511302e944f899b6025c68bf4ec6ffa920eedeec3f47a0
156 Risk Score

Malware Insights

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

The file was identified as malicious by ClamAV and an ML classifier, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised WordPress sites and disposable domains, suggesting an attempt to redirect users to potentially harmful content. The PDF's structure and the nature of the URLs strongly indicate a malicious intent, likely related to phishing or SEO abuse.

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://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160874d5a932ed---65082385790.pdf In PDF document text
    • https://cncostruzioni.com/userfiles/file/18833659015.pdfIn PDF document text
    • https://matrainagycsalados.hu/userfiles/file/nowaxutufefukopate.pdfIn PDF document text
    • http://etenindex.nl/images/uploads/nofonomofegag.pdfIn PDF document text
    • http://mybed.tw/uploads//files/202108060338558286.pdfIn PDF document text
    • http://abwingssuffolk2.com/uploads/files/notobozaja.pdfIn PDF document text
    • http://praxis-greve-polley.de/web/editor/files/19920055600.pdfIn PDF document text
    • http://kondicionery-domodedovo.ru/upload_picture/file/70242795533.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/7asm7ro20ndkhvn1ur66ud05l0/jefefedinibozagigokosud.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609219a0ad331---tomefadajuxoxutobinojuf.pdfIn PDF document text
    • https://limpiezasinasel.com/userfiles/files/69278667943.pdfIn PDF document text
    • https://baxsporthorses.nl/userfiles/file/zetuzegewiluxa.pdfIn PDF document text
    • http://rogo-rotterdam.nl/files/70469479045.pdfIn PDF document text
    • http://stjconsulting.it/userfiles/files/66113208561.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fb5a78754ba---59312680097.pdfIn PDF document text
    • http://konsultacjenaukowe.eu/Upload/file/25518128002.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b25c39277e0---gukisivoleremiz.pdfIn PDF document text
    • http://amtusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f3c24d46550---lirijapudedezaki.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/79614146735.pdfIn PDF document text
    • http://eia-edu.com/userfiles/file/daralijogadawovejis.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/kigelo.pdfIn PDF document text
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/d470f10923c8853b9395eade8ec8cadd/34478770730.pdfIn PDF document text
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6e0caac6a2---pujuzodid.pdfIn PDF document text
    • https://europacreativaeuskadi.eu/files/galeria/files/95098945213.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=make+full+sentences+using+the+past+perfect+continuous+and+the+past+simplePDF 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_off0000d2bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2BC 11252 bytes
SHA-256: 0e9886153c6e46b8a3d9776ad814928959f1197387353e0dd0382e1d319fad26
font_01_sfnt_off0000ecc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECC2 16180 bytes
SHA-256: 079f19b89ed800b03a4d791f2c2e7200a5aaaeed090dcb81678ab6aad99e8ebd
font_02_sfnt_off00011667.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11667 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1