Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ac91906818394b3…

MALICIOUS

PDF

83.1 KB Created: 2021-08-18 16:45:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 9a5922164b3b64956060b1a1a101d9dc SHA-1: 79b293c26e974acea4f52c211ea6c207d31c909e SHA-256: 8ac91906818394b38d75465afefd620a8f678ec72631d796d73db74338914ea6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous links pointing to compromised WordPress upload directories and disposable hosting sites, suggesting an attempt to distribute further malicious content or phish for credentials. Although no scripts were explicitly extracted, the nature of the links and the PDF's structure indicate it's part of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://yournew.site/wp-content/plugins/super-forms/uploads/php/files/9flsvuv8pegpndac3v2fpgqgti/gegolesajivog.pdf In PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/a3e224ff1beb3a0e61c60f3c19cc3ddd/lidawerodugu.pdfIn PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/ef938c90f9c4d729d9a11d5455147f88/7970703509.pdfIn PDF document text
    • https://arihantgranites.in/wp-content/plugins/super-forms/uploads/php/files/tm4eubm9j96vmirf24sc9nk974/94999632563.pdfIn PDF document text
    • http://hasici-pristroje-eshop.cz/files/file/sizomusodudejusajepamotoj.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160af235e45f98---52367272277.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/4881550675.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/4r1ckb9n8oreitc8i7v9o50ps2/67507678282.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/07b338083478f44da294335b92dcf7c8/litonobevezajagizupejale.pdfIn PDF document text
    • https://www.myosiaffiliate.com/199trust/img/file/gotopowumawek.pdfIn PDF document text
    • http://escritacontabilidade.net/fotos/news/file/famijavave.pdfIn PDF document text
    • https://www.americanapi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eab15500ce---23546911913.pdfIn PDF document text
    • https://aviseco.ro/userfiles/file/98165193653.pdfIn PDF document text
    • http://dijladentalcenter-qa.com/userfiles/file/4331766089.pdfIn PDF document text
    • https://nolimitscenter.be/peausitive/images/FCKeditor/file/zibajodirilufevewem.pdfIn PDF document text
    • https://danielstrehlau.com/userfiles/file/47344653695.pdfIn PDF document text
    • https://valerart.com/ckfinder/userfiles/files/lagepamuwu.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a6908c2fdf6---vebawizesufabivesemum.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/d38c5d539d122dd7a6986f7ef5428470/72461110541.pdfIn PDF document text
    • http://qa-whg.net/upload/files/kugomavekitopidu.pdfIn PDF document text
    • http://thaide.org/userfiles/file/xutelofezilugiwusifowevo.pdfIn PDF document text
    • http://www.supercarrentalsofmiami.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f882aa7c4d---69201053503.pdfIn PDF document text
    • https://rainbowfurnitures.com/files/files/28386263610.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/80918676828.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=manual+de+bizagi+process+modeler+en+espa%C3%B1olPDF 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_off0000de6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f681.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF681 17032 bytes
SHA-256: be5d741bb8155e58bc6a668ca2f5df1ef293193e3fe780fa85242cb0ce7d95f2
font_02_sfnt_off000121cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121CC 11260 bytes
SHA-256: 2f8902cc8229c4837b20f7e4ded4e940f9da7d57af221b73e1589ec6a4620d20