Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d173592dc5536da…

MALICIOUS

PDF

70.4 KB Created: 2021-09-12 14:36:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5cd680a2aad5f5694c0b300d17f5ff09 SHA-1: 0bcb1b125de7438bc2a00cdec8b85ecd7e2bdfee SHA-256: 4d173592dc5536dacbcfb7a1598434e91fdb1a2b5253cb774d5bfd16627ac879
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. Heuristics indicate the PDF acts as a link farm, pointing to multiple compromised websites and disposable hosting, suggesting an attempt to obscure the final destination. The ClamAV detection and ML classifier strongly indicate malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://medtravel.pro/images/hand_uploaded/files/rojemigonepezuwerega.pdf In PDF document text
    • http://tuzy.pl/Upload/file/nivadogobisozujo.pdfIn PDF document text
    • http://ikuma-car.com/js/upload/files/nipivadukatusutiniparu.pdfIn PDF document text
    • http://akademibt.com/resimler/files/91376742133.pdfIn PDF document text
    • https://nakshistudio.com/ckfinder/userfiles/files/gawidekulemimililevutal.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/xutifozifanokiwuzexe.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/161316b83228e6---pogukexifisufadiv.pdfIn PDF document text
    • http://ukrainski-rosyjski.pl/userfiles/file/57100241846.pdfIn PDF document text
    • http://allgeology.ru/ckfinder/userfiles/files/vubel.pdfIn PDF document text
    • http://www.novosib-sport.ru/ckfinder/userfiles/files/30578399193.pdfIn PDF document text
    • http://realtor-madrid.com/uploades/fckeditorfile/63995667243.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/9262686737.pdfIn PDF document text
    • http://www.ferm-matic.fr/upload/file/34054154667.pdfIn PDF document text
    • http://old.smartplus.pl/ckfinder/userfiles/files/64177715941.pdfIn PDF document text
    • http://novelinternationalschool.com/ckfinder/userfiles/files/1078792660.pdfIn PDF document text
    • http://areaengineeringsrl.eu/userfiles/files/61689903958.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d045f25cd8---38292366169.pdfIn PDF document text
    • https://hobbyschuurtje-webwinkel.be/images/userfiles/file/pinupexipefij.pdfIn PDF document text
    • http://bfcy88.com/uploads/files/lejuxadixopube.pdfIn PDF document text
    • https://kimcert.net/E/file/liwazovidafaserar.pdfIn PDF document text
    • https://carmelocuritiba.com.br/ckfinder/userfiles/files/2432158520.pdfIn PDF document text
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/cddecefcfcf08037fc079cabf12f324d/wixumaden.pdfIn PDF document text
    • http://okeefesreef.com/ckfinder/userfiles/files/balikujivimoxafubijekoj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=rupaul%27s+drag+race+season+12+free+onlinePDF 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_off0000b38f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB38F 15232 bytes
SHA-256: e3d959d5e0fed85adfa16630171f535c71b3d30218aae3b5676ab8494e1d6486
font_01_sfnt_off0000d9e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E3 11048 bytes
SHA-256: f72115415a354a0b1dca559975cd58b04fd8a354806f0a27b7f141d4b11066a7
font_02_sfnt_off0000f397.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF397 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1