Malicious PDF — malware analysis report

Static analysis result for SHA-256 66061b41ce1c19c5…

MALICIOUS

PDF

81.1 KB Created: 2021-09-16 05:22:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 5a7eec2599fe0fab9c47d2fa35b31739 SHA-1: 288890e9b67e90d69b07a2cba1b3945eee36a551 SHA-256: 66061b41ce1c19c520623da89fc0f9fa8f4465cf66968cb60adf10bd5b9c12aa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to potentially compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://castilloexterior.es/ckfinder/userfiles/files/10390161539.pdf In PDF document text
    • http://schodylux.pl/userfiles/file/nosamokenazimegesaboxefa.pdfIn PDF document text
    • http://snft.ro/media/file/91117934229.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16132d225689cd---sifudeso.pdfIn PDF document text
    • https://filetorme.com/upload/files/31554594250.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/43468843352.pdfIn PDF document text
    • http://hoteldanang.vn/uploads/images/files/fazuxupiwupukajo.pdfIn PDF document text
    • https://mcdelandes.ca/uploads/file/fatugefixeb.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141545faf894---sorilajibapadamigodabod.pdfIn PDF document text
    • https://mgc.to/sites/web/upload/files/46975166196.pdfIn PDF document text
    • https://nullemont.fr/nullemont/ckfinder/userfiles/files/20794321983.pdfIn PDF document text
    • http://0975811252cool.linker.tw/files/tovepezunevubij.pdfIn PDF document text
    • http://redigonda.it/userfiles/files/9092500459.pdfIn PDF document text
    • http://pepinieres-soupe.com/userfiles/file/kovedizeteran.pdfIn PDF document text
    • http://ed-union05.ru/files/file/75208431560.pdfIn PDF document text
    • https://polandpools.com/contents/files/sofavanoriwodutot.pdfIn PDF document text
    • http://recamonde.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161340849682c8---gamaxag.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/gegilegibunafosa.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/92301658691.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/69c6bbffc9308b3f9bf6661b5c592b1b/51192511265.pdfIn PDF document text
    • http://kkc1.org/htdocs/cljr/data/files/jibetubofekedimib.pdfIn PDF document text
    • http://henanshuangxin.com/d/files/xukod.pdfIn PDF document text
    • http://sibaco.ru/ckfinder/userfiles/files/58070930008.pdfIn PDF document text
    • https://mantyobras.com/userfiles/file/nafejusi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=android+applications+gamesPDF 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_off0000da37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA37 10836 bytes
SHA-256: e6a8d9e056966ad8076739e8edc7e9d9b7665df798b50016a61e1fbe7a0e42a4
font_01_sfnt_off0000f2fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2FE 16844 bytes
SHA-256: 96dc9f6bcc411178868a17749dc3fc84b5fe058ce53b539d83f05e7a3195aac1
font_02_sfnt_off00011eb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11EB5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1