Malicious PDF — malware analysis report

Static analysis result for SHA-256 f735ea74529302b2…

MALICIOUS

PDF

79.1 KB Created: 2021-09-11 13:41:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 879824c27492529aae153cd26dc656a7 SHA-1: c6dfcdbdd21d1f355b775a17079e71d2cd0b2e35 SHA-256: f735ea74529302b24f74fc943c9776e404a3334816fe2393f975802d6dda6877
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF was flagged by multiple heuristics as a link farm and by a machine learning classifier as malicious. It contains numerous URLs pointing to potentially compromised WordPress upload directories, suggesting an attempt to lure users to malicious content or phishing sites. The ClamAV detection of 'Pdf.Phishing.Trojan' further supports its malicious nature.

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.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613227646676b---82058529783.pdf In PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/vkqsoe508buo3c10ptr8t971e1/6484675911.pdfIn PDF document text
    • http://papaicountrylodge-longstay.com/user_img/files/3195039797.pdfIn PDF document text
    • http://allnatureint.com/userfiles/file/9485234141.pdfIn PDF document text
    • http://hotdeals24x7.com/ci/userfiles/files/webakamib.pdfIn PDF document text
    • http://lulanjina.net/upload/files/fejolekubevo.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333331871c7---48853378383.pdfIn PDF document text
    • http://coral-travel66.ru/admin/ckfinder/userfiles/files/wilozezexuwe.pdfIn PDF document text
    • http://tcsklife.com/filespath/files/20210906181528.pdfIn PDF document text
    • http://manilag.com/FileData/ckfinder/files/20210902_FA5C748E96D0FAEB.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f5813535bf---43090958296.pdfIn PDF document text
    • https://aronabritcan.com/userfiles/file/54688910085.pdfIn PDF document text
    • https://noukos.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16133cdaaf2d2b---17631024718.pdfIn PDF document text
    • http://armanetti.com/images/niwozapexofaxis.pdfIn PDF document text
    • https://tuoitre.bacgiang.gov.vn/lib/ckfinder/files/jewawedoregovet.pdfIn PDF document text
    • https://parisnordmedical.fr/docs/file/95454610024.pdfIn PDF document text
    • http://noithatachau.vn/webroot/img/files/59419252552.pdfIn PDF document text
    • https://path.mn/userfiles/files/37127818596.pdfIn PDF document text
    • https://lighthousemacau.com/html_upload/file/lupanijinisurubowipo.pdfIn PDF document text
    • https://kujainspectors.com/candyticket/uploads/page_images/files/kemejibexisokira.pdfIn PDF document text
    • http://caratow.nl/userfiles/file/49894878715.pdfIn PDF document text
    • http://chickendaylacrescenta.com/uploads/files/2364816007.pdfIn PDF document text
    • https://lazdynumokykla.lt/userfiles/file/92547291949.pdfIn PDF document text
    • http://chiron-ventures.com/chiron/home/img/upload/files/210909040347497145sgmp2.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=hide+my+ip+apk+premiumPDF 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_off0000d175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD175 17576 bytes
SHA-256: a488759c3dde97c4296024bae926d02cde2107b2225ed0926db7d3803b5fd483
font_01_sfnt_off0000ff6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF6C 10312 bytes
SHA-256: cf8053783e5d7b256aa435a82d4c2140e00d71a2876c2140fda17df8372efd04
font_02_sfnt_off0001169c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1169C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1