Malicious PDF — malware analysis report

Static analysis result for SHA-256 88bd6b71a9234425…

MALICIOUS

PDF

87.8 KB Created: 2021-06-29 04:06:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 82b3c1da63bfd8e8079f6076061a9e2f SHA-1: a4ae8b36034bd3d14c64753221058b8972215b7d SHA-256: 88bd6b71a9234425f4f70e97a2382a875be13c2d2a4ab0e832efb49216ee6210
156 Risk Score

Malware Insights

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

The PDF document contains numerous links pointing to compromised WordPress sites, identified by heuristics like 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, with ClamAV identifying it as 'Pdf.Phishing.Trojan'. The primary attack pattern involves directing users to external, potentially malicious, URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://smidgel.ru/uplcv?utm_term=hysterectomy+at+32
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7f667e916c---2968189108.pdf
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cec523f858---jikoxugam.pdf
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/43gqrlpmk7icm6rfoassn4sfq0/xujadesewifup.pdf
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607186379e744---siwunawinasifebisipusobap.pdf
    • http://capitolmetrophysicaltherapy.com/userfiles/file/faredavagofakezumuwum.pdf
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce3f6e0137---14097485658.pdf
    • http://deauville.ru/files/file/jivureb.pdf
    • https://papersacksfactory.ae/images/bulk_images/files/wadonitiwakoja.pdf
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/24bd9ca78b2f9eb7304a1f36501c4df3/murinukoj.pdf
    • https://alarrabnews.com/images/content/content/file/medowajoniba.pdf
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bfdf55ee066---malonuxevigupexo.pdf
    • https://eyetracking.pl/userfiles/file/80563762285.pdf
    • https://mecaniquekd.ca/upload/file/1214820731.pdf
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b9bd470afb8---70830221560.pdf
    • https://anmoul.com/userfiles/file/zusizituvamidumolurovi.pdf
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a13d3c20fa2---dusexasasis.pdf
    • http://anvlaw.com/userfiles/file/51466914824.pdf
    • http://kompletucetnictvi.cz/files/file/wogipezo.pdf
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f58f3ca130---tijodusewovol.pdf
    • http://fouladsazanco.com/Upload/file/86522559640.pdf
    • http://dlt-nkp.com/fileupload//file/69092685784.pdf
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/160b6b41d9eb52---nufobulam.pdf
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16086f9cf8825d---wezosavuveniw.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_off0000f4da.bin
353012dbbaf60ce085e762911e13d3fb873a4b547df2d65e042327c817db0e0a
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4DA 16852 bytes
font_01_sfnt_off00012090.bin
afed089c70ac25784460e539f324e21a41f3da0c60a0eca34ed89e4aa7a170fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x12090 10548 bytes
font_02_sfnt_off000138be.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x138BE 16792 bytes