Malicious PDF — malware analysis report

Static analysis result for SHA-256 b671a2a8d8a7340a…

MALICIOUS

PDF

73.4 KB Created: 2021-07-04 12:13:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: c6898b3e7e072aa401f924cde271266f SHA-1: 3688f803108f4fd4174156fd2b320e0333b35c98 SHA-256: b671a2a8d8a7340a95987c684be75e019599191011c336eb4620acbfc46cefe7
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing to multiple domains, many of which appear to be compromised WordPress uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The primary attack pattern involves luring users to external sites via embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607081d58b3ff---fatiru.pdf In PDF document text
    • http://liebherr-tr.com/userfiles/file/78571723701.pdfIn PDF document text
    • http://suttonoakfarms.com/clients/880813/File/67661894960.pdfIn PDF document text
    • http://leguido.net/files/takugo.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/16094733521e54---74267854415.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/e029ccc9cece5108ed88cd9d06fc3ceb/voxijexixezawebolew.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/f642013f8bfa1dd8831c9daac373b03b/vupukuz.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/v1pu3sltn3u4bmbhbotnl3hru2/35995661164.pdfIn PDF document text
    • http://mlsy.cz/images/file/files/37321225675.pdfIn PDF document text
    • https://jxloanchien.com/style/postimage/file/golexo.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608de9788575d---70835639515.pdfIn PDF document text
    • http://flexa.cz/docs/file/53667171236.pdfIn PDF document text
    • http://teckim.it/themes/userfiles//files/jedejumodabutoriki.pdfIn PDF document text
    • https://benjamindreyer.com/wp-content/plugins/super-forms/uploads/php/files/cfdc4849a31b1753981e9b5cbdb763d3/nezuzut.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/latawomugobub.pdfIn PDF document text
    • https://www.jscorporation.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160a38deec8608---32888858234.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/45776778172.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160886a539bf70---kinitotajinixudodejawesi.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16075e3ba92fb6---linas.pdfIn PDF document text
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/50769617257.pdfIn PDF document text
    • http://agro-vostok.ru/userfiles/file/49712659213.pdfIn PDF document text
    • http://recrute.fr/files/files/23372798478.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/b061192c30b69b13e5fce7bbd9ab4b2d/lowikuxilupidobojagapika.pdfIn PDF document text
    • http://atek-ent.com/upload/file/podatozudat.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/16945050105.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=multivariable+feedback+control+analysis+and+design+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_off0000b9f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9F7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d20e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD20E 11300 bytes
SHA-256: ab90a52191dd6ac740704b9947d6fc5b60d1d11f35bb641bf7306b61741b828b
font_02_sfnt_off0000ec63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC63 16888 bytes
SHA-256: d9f2f9101c6f259e2ded5e887c6a4ac948a9dadabcd163c144454883c0cea1f0