Malicious PDF — malware analysis report

Static analysis result for SHA-256 91f89d19d4f4d342…

MALICIOUS

PDF

81.9 KB Created: 2021-09-06 16:22:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ccbecee5b5dc24bfabfc0133efe873cc SHA-1: 77a08c4bd41e9fcefdd294cd0fadc37ec2c4c529 SHA-256: 91f89d19d4f4d3423cbffbb6964fba6b986a6a968cfb96fef4559bc45ed00bd7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting an attempt to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9933

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.artefuoricentro.it/js/lib/ckfinder/userfiles/files/67321225392.pdf In PDF document text
    • http://palaciodelosnavas.com/userfiles/file/novafipaxudozado.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce0e47af59---xoxabulusotod.pdfIn PDF document text
    • https://barcelona-health.com/files/galeria/files/jabovuwefome.pdfIn PDF document text
    • http://kredoteka.ru/uploads/file/66774601088.pdfIn PDF document text
    • http://staractivecollection.com/resimler/site/files/87813485266.pdfIn PDF document text
    • http://cosmeticdermatologymiamibeach.com/uploads/data/files/paketanadumunuxi.pdfIn PDF document text
    • https://episcopiaoradiei.ro/files/86445806219.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/bazoniduzom.pdfIn PDF document text
    • http://camwater.org/media/files/69752163730.pdfIn PDF document text
    • https://pinotcar.com/wp-content/plugins/super-forms/uploads/php/files/7bea5b207c90417ec89c45e6f35b3efb/55000951638.pdfIn PDF document text
    • http://breakevenpoint.pl/uploads/editor/file/38568438464.pdfIn PDF document text
    • http://china-zub.ru/userfiles/file/57829922832.pdfIn PDF document text
    • http://dellalontra.it/userfiles/files/lujidaxewavidemar.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077e48ae851e---rogodegoxuvoxebip.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/lipevekutubifunu.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/pegijov.pdfIn PDF document text
    • http://nemeckystrakac.sk/editor_uploads/files/63659570637.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/cc51l3dq94b1ipfkbmeq611pd2/buwowiwapuf.pdfIn PDF document text
    • http://compufoxmail.com/userfiles/file/28072008351.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/ac07735d5653e2a0c462c24b55d015d9/kezidevepilubibepegi.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/b040a78c92a9f9b0e7641f8cf86439f1/94099376759.pdfIn PDF document text
    • https://micast.de/wp-content/plugins/super-forms/uploads/php/files/h8vs9cpmrgf2qui6l1jhd588gd/lupitamesunanobisusorive.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/d41eae87afc6b3cc4874978d1f865611/foxesorofeperubinamo.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/e7fakrjtovrjmfp2npu8q2t2i3/94897576829.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=vishnu+sahasranamam+in+telugu+pdf+formatPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bb0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB0B 16240 bytes
SHA-256: f43886c219e357ae0829950373ee954979e1775f2bcf86dfc805193b30e3334a
font_01_sfnt_off0000d0f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0F9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e910.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE910 11012 bytes
SHA-256: 3bbccbfa68d04deadc1f50226fcc39b973edad1536e3a9172f149b359162731a
font_03_sfnt_off00010248.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10248 21596 bytes
SHA-256: 441bbecb7eaf03da3b058bae029a0dc02a4fde92ab32fbd9111e96ed82c553fc