Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6fb88dd63e0dbd4…

MALICIOUS

PDF

93.0 KB Created: 2021-09-19 17:06:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 0c3f3d1ab4622d1960e842331905b9a0 SHA-1: f8536100b93832e2c7c3bae1231f72bc491600fc SHA-256: d6fb88dd63e0dbd4a05bfc2c3717da7749020cddb42d299003c3629241958d93
156 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to infer the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://cructi.ru/uplcv?utm_term=a7+2017+custom+rom PDF link annotation
    • http://tcgardening.com/userfiles/file/2021091414224273499.pdfIn PDF document text
    • http://businessnavigator.in/ckeditor/uploads/files/rorowamagefonu.pdfIn PDF document text
    • https://cevhertemizlik.com/userfiles/files/43498200028.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021090401014473499.pdfIn PDF document text
    • https://equinox-e.com/upload/UserFiles/file/pikilotalopugel.pdfIn PDF document text
    • http://studioiulianella.it/userfiles/files/jedenemogepapiferosob.pdfIn PDF document text
    • https://vinocastillo.hu/editor_up/36146830055.pdfIn PDF document text
    • http://preiswerte-unterkunft-papenburg.de/mediapool/66695577093.pdfIn PDF document text
    • http://market-oborudovanie.ru/upload/file/47327877516.pdfIn PDF document text
    • http://intertribo.sk/files/rafoditewavebakasabikiwid.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/96676650595.pdfIn PDF document text
    • https://quimicasorocolor.com.ve/ckfinder/userfiles/files/zakozifapazoxal.pdfIn PDF document text
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614019456e519---11062057640.pdfIn PDF document text
    • http://bertoniamministrazione.it/bertoni/public/file/wobuwanomunanagonatimuw.pdfIn PDF document text
    • http://ubestsports.com/imager/files/20210910190856.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/letulokemelujerabuna.pdfIn PDF document text
    • http://baobianhkhang.com/upload/files/vunexezabewur.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/161417dd319dbc---57297373635.pdfIn PDF document text
    • http://travelsi.ru/ckfinder/userfiles/files/63510073527.pdfIn PDF document text
    • http://tpt.taipei/asset/uploads/files/34639251888.pdfIn PDF document text
    • http://china-hold.com/UploadFile/file/20210911130208302.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/vezonurulebodunabuzixev.pdfIn PDF document text
    • https://4wheelchile.cl/admin/uploads/file/41822437756.pdfIn PDF document text
    • http://phutungotodungha.com/img/files/ramedoruforapogifujufabis.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/733afhr7aibc01tp6vl312g2av/ruxobuginovibusu.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_off000101ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101AD 10280 bytes
SHA-256: daeb75a5ac0e782ebcd310a675f6cc41ab4b3148ed2159554a13d46e0fbaa920
font_01_sfnt_off0001190b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1190B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001311d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1311D 20120 bytes
SHA-256: 075849403e10dda9af86ff13d2dd24ab8a4e5abf0b6c53ebcf63cfbc0df6f95f