Malicious PDF — malware analysis report

Static analysis result for SHA-256 e28aa994b9b11853…

MALICIOUS

PDF

74.1 KB Created: 2021-09-11 14:14:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a8d613eb95eaf058787d634d6dd43c35 SHA-1: 296dfa6ec635531f66d6ac67ffdabdee32624252 SHA-256: e28aa994b9b11853381ca527ba54fcf8d1cab24605cf9378abbb7ae8644555b1
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous external PDF files, many hosted on disposable domains or compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were directly extracted, the structure suggests it's designed to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://precisao.org/files/files/vimiwuwefepavupolula.pdf In PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613679b019a5d---71261608344.pdfIn PDF document text
    • http://rickgrisolia.com/userfiles/files/98527939801.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/l84mdvptetj7vda3emogkivqcr/kafadufamaxip.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/6bdfc03842f54bd048b9bba5601e925b/65110926063.pdfIn PDF document text
    • https://ixiu-23.com/uploads/files/202109072353453933.pdfIn PDF document text
    • https://kibledergisi.net/resimler/files/58597163181.pdfIn PDF document text
    • http://feach.ie/images/uploads/file/55200859587.pdfIn PDF document text
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/mepaxudasuwokito.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109012205476273.pdfIn PDF document text
    • http://koopmankennedyfeller.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nonimogoxufamomej.pdfIn PDF document text
    • https://fibaquitaine.fr/cebatrama/userfiles/files/34569900608.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/gumeworisasi.pdfIn PDF document text
    • http://belgium-ex.com/images/blog/file/kebatilatadopoworo.pdfIn PDF document text
    • http://vnos.vn/app/webroot/uploads/files/xiresikuvegaleral.pdfIn PDF document text
    • http://machulski.com/public/file/rejevifugana.pdfIn PDF document text
    • http://robbes.nl/media/files/wavola.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/ronovejavuvefixupowejiwu.pdfIn PDF document text
    • https://winstar-tools.com/UserFiles/editor/file/foridipogibakujuzamenuvav.pdfIn PDF document text
    • https://parklanehotel.asia/userfiles/file/fibenazibejurofisova.pdfIn PDF document text
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/muwoledugokitowu.pdfIn PDF document text
    • http://brianhaymore.com/images/e/file/masipitutevujerumuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=dominus+promo+code+2021PDF 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_off0000bedb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEDB 16568 bytes
SHA-256: 4f04a68df36a865c73e9a089379b20ba64573c9e44fc308b5f59d215d80dc461
font_01_sfnt_off0000ea0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0C 10764 bytes
SHA-256: 3ecb0877182f9226e8bcb66fc2c2f521752852deac9661b7d1daa157f822638f
font_02_sfnt_off000102d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1