Malicious PDF — malware analysis report

Static analysis result for SHA-256 643280626b872274…

MALICIOUS

PDF

71.5 KB Created: 2021-09-15 03:03:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5717a3b7f024ac74095493d858cf2910 SHA-1: bc0ae223678b721772d0cc6451995d2c0e4d1111 SHA-256: 643280626b87227408cb9b6e14802755f99e991b8c5d3522a40127f1ec96ec2d
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to compromised websites and disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple compromised CMS upload links further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://creativenursery.net/home/creative/public_html/ckfinder/userfiles/files/zazetufemijifilaw.pdf In PDF document text
    • http://hmed.vn/upload/files/29264753215.pdfIn PDF document text
    • https://ibshospitals.com/userfiles/file/45365565504.pdfIn PDF document text
    • http://clinicaveterinariabilancino.it/userfiles/files/34031071898.pdfIn PDF document text
    • https://cdmsig2.com/ckfinder/userfiles/files/90833537175.pdfIn PDF document text
    • http://synthecinter.com/userfiles/files/volazorewitidasojeka.pdfIn PDF document text
    • http://www.caribbeandentist.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141215e7bb9a---voporagekide.pdfIn PDF document text
    • http://ordineveterinarivenezia.eu/userfiles/files/mawewot.pdfIn PDF document text
    • http://daotaoyduoc.org/wp-content/plugins/super-forms/uploads/php/files/657ca8714438a3245bb75ca1c6b3fffd/zixugosaw.pdfIn PDF document text
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/5e2d7c0ceb0945539af1209aa26eedb1/pitotepefus.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/90718767501.pdfIn PDF document text
    • http://www.mousumibanerjee.com/fckimages/file/29453415039.pdfIn PDF document text
    • http://doks-films.com/pcms/content/file/muwarirefitegevolasenal.pdfIn PDF document text
    • https://bednidhitraders.com/userfiles/file/bonifavibavorudijotetuna.pdfIn PDF document text
    • http://julianina.dk/upload/file/40179192696.pdfIn PDF document text
    • http://beta-rc.com/upload/files/88178999136.pdfIn PDF document text
    • http://desiaussies.com/ckeditor/uploads/files/sevapiwigim.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161312c4b31345---14123263734.pdfIn PDF document text
    • http://julianowka.pl/ckfinder/userfiles/files/dorejozetesemiguwatubive.pdfIn PDF document text
    • http://ztracenaexistence.cz/files/content/file/raduwepezuwimaxosu.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/e5e3ebd2361c20cb8bb38979e791767c/91514825383.pdfIn PDF document text
    • https://muacash.com/webroot/img/files/25330404001.pdfIn PDF document text
    • http://lachambredechos.com/userfiles/file/677809456.pdfIn PDF document text
    • http://zimmerei-possert.at/98852829915.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/91b216f02049b4366f2d2f3961f7f659/39426254188.pdfIn PDF document text
    • http://kavernoklub.com/campannas/file/gekuxifilimemetofege.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=mod+hack+mini+militiaPDF 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_off0000b976.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB976 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d188.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD188 15772 bytes
SHA-256: d0d8f28b5f077f26314af944d9a78a06e67c9c1d5881713781aa3ed61bff047a
font_02_sfnt_off0000f9af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9AF 10320 bytes
SHA-256: bcc1a30c929a31501a45eb5528fa13b4dd7cdbfd04d345696d61a87df8b3bad2