Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b19f3dd60dd760a…

MALICIOUS

PDF

81.2 KB Created: 2021-09-19 00:01:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2b8a42f2fba2553d794b14d6a4ff10eb SHA-1: a25e23665e715c7a4933b4bf074750678b89c1c0 SHA-256: 4b19f3dd60dd760ac65258f2ac6661889849f39b5fd960c41fb872e2b8553785
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous links, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a common phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://huntic.ru/uplcv?utm_term=english+conversation+practice+exercises+pdf
    • https://geniodelweb.com/file/61700032938.pdf
    • https://sooryasales.com/uploads/file/10662681551.pdf
    • http://quatanggiabao.com/images/uploads/files/jatelisupuzijewaxisiroge.pdf
    • https://baust.edu.bd/app/webroot/ckfinder/userfiles/files/debazuvapudozat.pdf
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea61312c18---22779978930.pdf
    • https://egc.ecrom.work/syo/files/35785395539.pdf
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/lenosagagupopu.pdf
    • http://masterkontroll.hu/ckfinder/userfiles/files/23104692853.pdf
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/161400dc259060---46567922453.pdf
    • http://eva.am/files/2ec795a4ebb673fd.pdf
    • http://acsalma.hu/userfiles/files/48829598246.pdf
    • https://rcot.org/userfiles/file/3079215040.pdf
    • http://pogologistics.com/ckfinder/userfiles/files/37091059689.pdf
    • http://www.ville-dammarie.com/ckfinder/userfiles/files/3244479899.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613be117b9f56---35837549774.pdf
    • https://moniimpex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137c71f1c052---jepolelokurada.pdf
    • https://a-pointpro.com/cms/ckfinder/userfiles/files/wawoxagaduluxo.pdf
    • http://www.integra-cr.cz/administrace/ckfinder/userfiles/files/jolikedagofawunev.pdf
    • https://xn--lenachatka-57b.pl/uploaded/file/nobixexebuw.pdf
    • http://www.asiacoservice.com/file/files/vigimudi.pdf
    • http://gioiacompany.net/images/upload/file/85108636517.pdf
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141b6f59bd66---nerejevetikavefajixu.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d5ef.bin
126c515d479aae8c149df93d32aab94ba154f81a1430447f24beb5caa6d9423f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5EF 18464 bytes
font_01_sfnt_off00010580.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10580 16792 bytes
font_02_sfnt_off00011d97.bin
97dedc7cc9270d30e259339a453d3a4a84957636ff0e230c54171f21011f8ae4
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D97 11052 bytes