Malicious PDF — malware analysis report

Static analysis result for SHA-256 24e756a74cc1866f…

MALICIOUS

PDF

74.8 KB Created: 2021-08-10 09:32:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 83ccf61ccc67697aa105c3110bd86db3 SHA-1: 31e1eb60dacf0bf20573c254b19cb04a398bf97f SHA-256: 24e756a74cc1866f00c3896f8d36ca29a9a2b478053516aef52cbaa7c78bb608
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The document body is unreadable, but the heuristics and URLs strongly indicate a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://esoftland.com/userfiles/file/2312653181.pdf In PDF document text
    • http://stonestudio.pl/files/upload/file/gujogifivowigubox.pdfIn PDF document text
    • http://churchliferesources.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608f02e479489---vujazonajo.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16071bc6a9972d---ranizaxeluxija.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/56ad2d8584d68570d031b8e5a813d81e/48878656835.pdfIn PDF document text
    • http://urduhadith.org/survey/userfiles/files/muvegojirewibixifijo.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085694e91837---58381977836.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/25409220630.pdfIn PDF document text
    • http://chelseafoodmart.com/uploads/files/53762669384.pdfIn PDF document text
    • https://acrgroup.nl/userfiles/file/9959742351.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a41b32bb3c0---32842486978.pdfIn PDF document text
    • http://galettedesrois.hu/userfiles/file/36167660526.pdfIn PDF document text
    • https://weblative.com/wp-content/plugins/super-forms/uploads/php/files/n895tfnfc5b17aic6n55lg7aeq/nosudaperupi.pdfIn PDF document text
    • http://robertoantoniz.com/resources/original/file/26312752932.pdfIn PDF document text
    • https://arbormaster.net/uploads/files/zovufij.pdfIn PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/jejito.pdfIn PDF document text
    • http://pkynfe.net/userfiles/file/jexikikigused.pdfIn PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/65ea67a05813ae63cb9e6b07edf9ac86/ronupixivigikepezudar.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/121f010413d2282452e246e279221330/94583078339.pdfIn PDF document text
    • http://www.brickchamber.com/ckfinder/userfiles/files/jofojid.pdfIn PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/s1rpk7hrbkik68v385e57p1r9c/36402676877.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eba3c13357---lekumezeteze.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607fcdbc7d1a4---birekanafiperemuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=principles+of+human+anatomy+and+physiology+tortora+12th+edition+pdfPDF 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_off0000c042.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC042 16156 bytes
SHA-256: 38553d15c79edf912a8584066a78775305bd8e21d52e8255da97520d0900cc19
font_01_sfnt_off0000e9cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000101e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101E6 11452 bytes
SHA-256: 04b2bbf624977b25193becd9270ab1b47cd4a257125c9b3079d5a4b556188402