Malicious PDF — malware analysis report

Static analysis result for SHA-256 ceccd6482e0c9502…

MALICIOUS

PDF

84.6 KB Created: 2021-10-08 04:24:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6b00a01700495f5d11111785fd55a40e SHA-1: f15f4012d3a58a4db52788fea073cbbf67ca1484 SHA-256: ceccd6482e0c9502a0dd0f9bf2b83c3a1cdc6cc66389da76f2805bdd65763cd6
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple distinct hosts, some of which are compromised CMS uploads. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a vehicle for the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.moxiclear.com.au/application/third_party/ckfinder/userfiles/files/babelarabuve.pdf In PDF document text
    • http://eternaseguros.net/files/files/5667367046.pdfIn PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/66181638781.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/bebexasare.pdfIn PDF document text
    • http://s4l.vn/storage/ckfinder/files/86142706806.pdfIn PDF document text
    • http://outspokenholland.com/userfiles/fckFile/20210906233415.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614053c76e976---soxejakesototoxo.pdfIn PDF document text
    • https://mklaassen.nl/images/file/xefevinomadol.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134fdb4dd77d---24246150126.pdfIn PDF document text
    • http://bearings-home.com/userfiles/file/farurovejumonewob.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615aa2fc3c90c---tijibolofiperuwedasasip.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/xexovejakujedodowave.pdfIn PDF document text
    • http://gardatrans.com/content/Files/pojujetopukujowi.pdfIn PDF document text
    • https://iamtimeshare.com/userfiles/file/79800168749.pdfIn PDF document text
    • https://olterus.net/contents/files/fegasifodapodax.pdfIn PDF document text
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/97302040332.pdfIn PDF document text
    • https://samarthanamparisara.org/apadmin/uploads/userfiles/files/ralawazewuxevixus.pdfIn PDF document text
    • https://n-vv.dk/userfiles/file/56929324261.pdfIn PDF document text
    • http://utcsp.rustyramone.com/uploads/files/fogixutizevutiwokapifagi.pdfIn PDF document text
    • http://megalabsrl.it/userfiles/files/jugaxobijuzagexe.pdfIn PDF document text
    • https://sayurmateng.com/contents/files/wekes.pdfIn PDF document text
    • http://diagnosticaedilizia.com/userfiles/files/7761910912.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/xatebivus.pdfIn PDF document text
    • http://tischtennis-kiel.de/images/file/dovor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=three+branches+of+powerPDF 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_off0000e676.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE676 10528 bytes
SHA-256: bf90fc08edc96bb69a4f0bb6fce304031e3be75bddcd614d0d70c8a41e9117fe
font_01_sfnt_off0000fe3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001164c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1164C 18196 bytes
SHA-256: 9a7b04f4d5ca954812a17e7c52a61a7b208e91fd262801f2cf8c074dbb491ca2