Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c8a521bbd239ba0…

MALICIOUS

PDF

89.3 KB Created: 2021-09-04 16:34:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3843c2f0f0bec74455189bfbee44753d SHA-1: 77ea249ed7a6a412d67f38dee89806fd1ca1f882 SHA-256: 0c8a521bbd239ba0b8631282047f99ca55e4f982c6f57f79682cb89b01be4fd6
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. Several heuristics point to the document acting as a link farm, directing users to compromised CMS upload directories and potentially disposable hosting sites. The embedded URLs, while some are marked benign, are part of a larger pattern of redirection that is characteristic of phishing or malware distribution campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7ae8b19e21---16483700398.pdf In PDF document text
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/26749437440.pdfIn PDF document text
    • http://massageindex.nl/images/uploads/57940999754.pdfIn PDF document text
    • http://circuitvietnamcambodge.com/hinhanh/file/kutuzuwipupumalefewax.pdfIn PDF document text
    • https://nhanloc.net/userfiles/file/82997360151.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/zidexunudafazural.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bfc34b3b20---49231165412.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f3a3d95a1c---65513998038.pdfIn PDF document text
    • http://w-f-l.de/user_img/file/rudubumaxuz.pdfIn PDF document text
    • http://www.contectrade.hu/fckfiles/file/99234938950.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/files/54872698940.pdfIn PDF document text
    • http://xycrusher.com/d/files/97823581985.pdfIn PDF document text
    • http://euredit-editions.com/userfiles/file/58904982895.pdfIn PDF document text
    • http://caudafotografia.com/userfiles/files/pupizofafexekepe.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160bda3cf04816---lofuk.pdfIn PDF document text
    • https://hiddencliff.kr/FileData/ckfinder/files/20210713_CD1BD331A1AFF48A.pdfIn PDF document text
    • https://www.sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608be9710c504---nezijazonevogowo.pdfIn PDF document text
    • http://meadescafe.com/userfiles/file/pokalo.pdfIn PDF document text
    • https://pelicanfinancialnetwork.com/ckfinder/userfiles/files/63190586749.pdfIn PDF document text
    • http://endustriyelkiralama.com/wp-content/plugins/super-forms/uploads/php/files/9236l7hlh1mmchhij0ucug6rnc/fowaxiridumubonosaz.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608e6d130ac80---58841419979.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16084f51276013---32126461334.pdfIn PDF document text
    • https://mimpidia.com/contents//files/munijikexosutikofikokesi.pdfIn PDF document text
    • http://studioguagnoni.it/userfiles/files/12726931521.pdfIn PDF document text
    • http://qunjl.com/userfiles/files/61284067347.pdfIn PDF document text
    • https://bluza-shop.ru/content/File/41371745997.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+compare+2+worksheets+in+excel+2013PDF 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_off0000f3e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3E9 18828 bytes
SHA-256: e679bfe31008c67c78bb2213473a45e1db58c0664a6fa35fac4e090806ea1df4
font_01_sfnt_off0001249c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1249C 11376 bytes
SHA-256: a3a5a251299a4a5cbf3be623f0f58546e757fc1113571a6bec45d8391e0f5f9c
font_02_sfnt_off00013f68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1