Malicious PDF — malware analysis report

Static analysis result for SHA-256 5216d6b3ec329cdd…

MALICIOUS

PDF

81.3 KB Created: 2021-09-23 03:20:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 3727f15ba3c21ec3e505e71d1399aee5 SHA-1: 764e43e3fd49aea79830a1af9d7120d8fe48fb08 SHA-256: 5216d6b3ec329cdd6bde25b4341bec7c3d5392b77a6b2345d8c5ebacba9948e8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF document was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. It contains a link farm with numerous URLs pointing to potentially compromised websites, suggesting an attempt to redirect users to malicious content. The presence of multiple 'link farm' heuristics further supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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 http://mexxeopaint.com/upload/files/1714116719.pdf In PDF document text
    • https://millersexpress.com/userfiles/file/6217702470.pdfIn PDF document text
    • http://kientrucnhacuagio.com/upload/files/70028149082.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/temisaverokobaxepafodi.pdfIn PDF document text
    • https://rimsball.com/ckfinder/userfiles/files/retexetibefev.pdfIn PDF document text
    • http://nocleginaplus.pl/uploads/userfiles/files/wededikulejinufap.pdfIn PDF document text
    • http://dkmmotor.com/files/userfiles/file/50424654545.pdfIn PDF document text
    • http://farmaciafoglia.eu/userfiles/files/2588388009.pdfIn PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/9f7c7b84679af81e0d1a8fb9bb1f83ae/93939835910.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/suzukimiziwunisesajive.pdfIn PDF document text
    • https://aptitudeclass.com/ckfinder/userfiles/files/78838605030.pdfIn PDF document text
    • http://alteredcompta.com/buddha/ckfinder/userfiles/files/53012441639.pdfIn PDF document text
    • http://thsport.dk/ckfinder/userfiles/files/guburad.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/p8rvn3kpl72a345srllsr66mu3/sixadosufidavezasaxi.pdfIn PDF document text
    • https://rcvizovice.cz/ckfinder/userfiles/files/negatejogan.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/5429840778.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/1614097732f865---22746963232.pdfIn PDF document text
    • https://tselectromechanical.com/uploads/CKfiles/files/30115298703.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/161435b48262ff---gagazujufugefiwubeka.pdfIn PDF document text
    • http://pmdrecycling.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3bb304a46---daweruwufabu.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210920211441_gse7y1.pdfIn PDF document text
    • http://knuhpharm.kr/userfiles/file/20210907181024.pdfIn PDF document text
    • https://premiersuli.hu/files/files/85123323960.pdfIn PDF document text
    • http://youil.org/userData/board/file/73451245365.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=gta+v+cheats+pc+helicopterPDF 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_off0000d86a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD86A 18108 bytes
SHA-256: 4aa337568287a2db7c4dd80f23a2339b3307a7f32d6d8cdc490bd722c75ee92e
font_01_sfnt_off000107a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107A8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FBF 10472 bytes
SHA-256: 858d55fd86be1a6b4a1f1fbad61bd6bca9d51725d3085741b457092e21d9758e