Malicious PDF — malware analysis report

Static analysis result for SHA-256 4eb109ffe81ef0c8…

MALICIOUS

PDF

80.9 KB Created: 2021-09-13 16:19:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b3c3e2fae99f57bae9eda01e0e866171 SHA-1: 1c94249e6fb4d1239f49ccf90bd7c61a56864942 SHA-256: 4eb109ffe81ef0c85857b1c2a08beb66e41d77e8042ef930d3b58eb939b139ee
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to other PDF files hosted on various domains, indicating a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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://irlanc.ru/uplcv?utm_term=the+four+hour+chef+pdf PDF link annotation
    • http://mq-water.net/upload/kupujadizimubupomeb.pdfIn PDF document text
    • https://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613333982908b---wusoboja.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/xizid.pdfIn PDF document text
    • https://celebicatering.com/upload/ckfinder/files/19661443800.pdfIn PDF document text
    • https://hotelreviewreserve.com/basefile/hotelreviewreservecom/files/kiribominixe.pdfIn PDF document text
    • https://glycocalyx.nl/userfiles/image/file/19793068208.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/pirunukezulivanu.pdfIn PDF document text
    • http://rollfactorytogo.com/uploads/files/12301759358.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/1b67353fc67edcaf44792d2701476a1d/nutekiselakiximaver.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/pavilozijifom.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16138685d7b7b1---77052876196.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613245aa2b8f3---vugozifeganejev.pdfIn PDF document text
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/1613e601001ddc---rikedusujagakasema.pdfIn PDF document text
    • http://eortak.com/img/fck_temp/file/vadupusu.pdfIn PDF document text
    • http://simkoongschool.com/uploads/editer/files/jasax.pdfIn PDF document text
    • https://lionkingbali.com/uploads/file/88875661695.pdfIn PDF document text
    • https://pensiuneaselina.ro/userfiles/file/58859730098.pdfIn PDF document text
    • https://sma-dfgg.org/site/admin/file/pijab.pdfIn PDF document text
    • https://4wheelchile.cl/admin/uploads/file/pomifizaxuxefiwupuwu.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138fba929998---xafumupisigepememu.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/xazumokamikinokabej.pdfIn PDF document text
    • http://coolscape.info/images/files/29842771558.pdfIn PDF document text
    • https://wronba.pl/uploads/wysiwyg/file/venapuraburinewapev.pdfIn PDF document text
    • https://anakmeong.com/contents/files/gulizazuwezugudikunal.pdfIn PDF document text
    • http://klasykarozrywki.pl/public/images/fck/file/16687085945.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/dqj76g0sl8npe1010206nvsusi/2698364840.pdfIn PDF document text
    • 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_off0000d93e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD93E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f155.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF155 10112 bytes
SHA-256: e3d6178f697602509449440b63ff46baa84da6c2235d821f5d1840e7ace0a58c
font_02_sfnt_off000107f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107F4 17920 bytes
SHA-256: 49645cc64110e34085bb22625f5bd1091d1e00d2121d2847f2466d8ec2061b59