Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f8d19082dc00e83…

MALICIOUS

PDF

72.4 KB Created: 2021-09-23 07:01:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f070f3f04923cdffb90a555cced65c5c SHA-1: 442be54d64854dcc2da22668b5b65d76daf4ee2d SHA-256: 8f8d19082dc00e83688625b4d1922b4a39e6415b2dfa4221dc4c9164e4b8f126
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to other PDFs hosted on compromised websites. Heuristics indicate this is a link farm designed to distribute further malicious content, likely for phishing or malware delivery. The ML classifier and ClamAV detection strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://weblative.com/wp-content/plugins/super-forms/uploads/php/files/lc8eees1pavu9mlfgk3ghohq2g/rasukituxojojesonirokade.pdf In PDF document text
    • http://knipia.com/userfiles/file/67252739923.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f3f2377b68---fidekumonozefenodal.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/95329695508.pdfIn PDF document text
    • https://soechi.id/userfiles/file/wapinofasumuta.pdfIn PDF document text
    • http://myappartement.de/web/editor/files/pinutivebijomumixotasog.pdfIn PDF document text
    • http://delfosventures.eu/userfiles/files/kerapimubenikunorabip.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/56966491631.pdfIn PDF document text
    • https://concurs-euclid.ro/upload/fck/14214581526.pdfIn PDF document text
    • http://ilonew.tasksplan.com/ckfinder/userfiles/files/fizivubefagilubara.pdfIn PDF document text
    • https://processwork.archerhuang.com/ConImg/files/xefujosetumewud.pdfIn PDF document text
    • https://www.highettmetal.com.au/application/third_party/ckfinder/userfiles/files/32717579524.pdfIn PDF document text
    • https://ratoempat.com/contents/files/23312009300.pdfIn PDF document text
    • https://anne-berger.de/sites/anne-berger.de/files/fkcfile/kigogedalulonubaxebegos.pdfIn PDF document text
    • http://ciaomamma.hu/editor_up/75311580149.pdfIn PDF document text
    • http://ratchee.com/ckfinder/userfiles/files/60329101291.pdfIn PDF document text
    • https://picinterior.com/ckfinder/userfiles/files/65402673963.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/88250111000.pdfIn PDF document text
    • http://geotersrl.it/file/dilideg.pdfIn PDF document text
    • https://christianbelieversmatrimony.com/web/christiansbelieversmatrimony/photos/ckeditor/files/44374317697.pdfIn PDF document text
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613e45d7f3863---nuliti.pdfIn PDF document text
    • https://sooryasales.com/uploads/file/23698948473.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=glee+karaoke+volume+3+song+listPDF 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_off0000b800.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB800 16636 bytes
SHA-256: 50524362b8a10e4a2572d57e8b9dfb0f9d5531bf3eb1b41147d1279dc9982d19
font_01_sfnt_off0000e286.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE286 10920 bytes
SHA-256: 883c0c4f2b8411ab08e5ec7046ca9b60f4c94de716be3891f183f517fcda2040
font_02_sfnt_off0000fbe6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1