Malicious PDF — malware analysis report

Static analysis result for SHA-256 75ecfb18a1ac9937…

MALICIOUS

PDF

77.2 KB Created: 2021-09-05 09:00:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 4a0f54a8a8a31920f65c06cf1a8107cd SHA-1: a4e93730d77fce301a4f6953447ad28ea880de56 SHA-256: 75ecfb18a1ac99379c5aaadafdf05d69a0b6ee6613d9d6a97210a2d25b2a4386
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm or phishing lure. While no scripts were explicitly extracted, the presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates the document's primary function is to redirect users to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://nomylo.ru/uplcv?utm_term=first+certificate+in+english+1+cambridge+pdf PDF link annotation
    • http://artpolyclinic.com/file/files/13398287362.pdfIn PDF document text
    • https://transport-vehicules.fr/userfiles/file/79748786103.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8e0fca94da---tugofarilareja.pdfIn PDF document text
    • http://kxnjl.com/userfiles/files/95224270361.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/ogo5meah7db4k45bnf9dd6squp/71355454399.pdfIn PDF document text
    • http://tl-maskinfabrik.dk/userfiles/file/bolukozovojidapijepareze.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/268c0f2201ab9b9b033a5dc88dd8ca59/92304621819.pdfIn PDF document text
    • https://bilalyapidekorasyon.com/userfiles/file/werebemizefixakig.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/40622818733.pdfIn PDF document text
    • https://nodka.eu/ckeditor/ckfinder/userfiles/files/86639640259.pdfIn PDF document text
    • http://www.ufolep-69.com/contenus/files/78622440553.pdfIn PDF document text
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16121cc405bb91---44145635803.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608243459c7d5---gelosapoka.pdfIn PDF document text
    • http://jagatjyotischool.org/jagatjyotischool/userfiles/file/gevogusukexiwi.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16082a63394723---93018080976.pdfIn PDF document text
    • http://msci.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1607f972bdea80---47339364858.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/6481087982.pdfIn PDF document text
    • http://aquarium-kochi.com/app/webroot/ckfinder/userfiles/files/78839729850.pdfIn PDF document text
    • 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_off0000c21c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC21C 20380 bytes
SHA-256: 71754f15cb3cff313ef53227fe15ed7d598b9cbf40eb02c513c078f75cfdcda5
font_01_sfnt_off0000f5be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010dd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DD5 11116 bytes
SHA-256: f0f5b2d90019c0c537b33a392d5e7699aff71eecadbeb754154fb7de0ce6ffca