Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f436a95c5473e35…

MALICIOUS

PDF

92.8 KB Created: 2021-06-10 11:41:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 9759a6882badbff1756ff19240e5dea6 SHA-1: 2fdca9b230ec065093227ab76a092135e7038008 SHA-256: 3f436a95c5473e351c0661ac6dae1ad418d362e5ca213ba1d1005a6f94fe3e99
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded links pointing to various domains, many of which appear to be compromised WordPress sites. The presence of a link farm and a high ML classifier score indicate malicious intent, likely for SEO manipulation or phishing. ClamAV also detected this file as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://inwebjor.ru/uplcv?utm_term=find+the+missing+side+of+a+right+angle+triangle+calculator PDF link annotation
    • https://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091c048eba69---56900090487.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/60c7332849529514b24059743ee2835b/sopukiguxiviwividax.pdfIn PDF document text
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/c69ac2f093f8c4b8df843e00c7766b4e/47422252056.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/b8360cb6e18d400dcb1594013d64a50d/fusesapirulaletejixe.pdfIn PDF document text
    • http://portalcom-b2b.es/img/user///file/_0444815001620298652.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/cr0bkj961otgkdgcft96pehlp4/30052782139.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a5a856a5c82---80925724707.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/fa11482b73276b87740d3b0d98b77f16/namowedojosipobepumirejut.pdfIn PDF document text
    • http://kagoshimakojintaxi.com/userfiles/file/kififefir.pdfIn PDF document text
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160828b7586268---retigofemo.pdfIn PDF document text
    • http://ixtvs.de/_upload_bilder/_filemanager/file/xofuguzadexos.pdfIn PDF document text
    • http://school19-zav.ru/userfiles/file/36596028175.pdfIn PDF document text
    • http://milcontabil.com.br/wp-content/plugins/super-forms/uploads/php/files/3rlvbbh1v1mv4a5k6gtc86tt17/dozegesapumutin.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606ffb0ecfa27---kowivadazasebeziditi.pdfIn PDF document text
    • http://dragonera.cn/admin/userfiles/file/judamatulow.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12882 5392 bytes
SHA-256: bad2fb7f9a4c26773dc7f075c6e7e13c656761bda589a13f62116cb067c842d9
font_01_sfnt_off00013aab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AAB 12824 bytes
SHA-256: 70262e4cd31f745a713a5cf0a5b6d3ae162cf57bed6f76be081198713ba9631d