Malicious PDF — malware analysis report

Static analysis result for SHA-256 87cfd042475c39ac…

MALICIOUS

PDF

82.8 KB Created: 2021-09-19 08:58:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8fe1cba3e76ff2b44ac354be3f4b39a3 SHA-1: f0d1ab1475c5930aa0d79081b0792391a39ea7ba SHA-256: 87cfd042475c39ac1034dc1ce4b47500525908204f460ceee5e68cdcd1d770ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to multiple distinct hosts, some of which are compromised WordPress uploads or disposable hosting. The presence of numerous unknown URLs suggests an attempt to distribute or host malicious content.

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 http://www.emploi.nat.tn/ckeditor/ckfinder/userfiles/files/goxakuwaxabudizaxozaj.pdf In PDF document text
    • http://ros.by/ckfinder/userfiles/files/97298525227.pdfIn PDF document text
    • https://marblo.ph/app/webroot/img/files/94803282711.pdfIn PDF document text
    • https://bushregenerators.info/userfiles/files/jawovuboga.pdfIn PDF document text
    • https://perfectsextherapy.com/public_html/userfiles/file/muluzisasatuleji.pdfIn PDF document text
    • https://testpensija.bankai.lv/ckfinder/userfiles/files/tamewuzugetuvuji.pdfIn PDF document text
    • https://floridahouselottery.com/test/userfiles/file/pijuba.pdfIn PDF document text
    • http://asremajazi.com/uploads/files/gesuk.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613df4062a343---54943408917.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/kuzukem.pdfIn PDF document text
    • http://arunimaflavours.com/userfiles/file/zulenorerorawomipoka.pdfIn PDF document text
    • http://dealershop.es/camarasegovia/userfiles/file/30852893108.pdfIn PDF document text
    • https://dadesigning.com/daduserfiles/files/35479430252.pdfIn PDF document text
    • http://thebankcardservices.com/uploads/files/38140027274.pdfIn PDF document text
    • https://theloneranger.tv/clients/loneranger/ckfinder/userfiles/files/seledineviwu.pdfIn PDF document text
    • http://wawa757.com/uploads/files/wazawuxepevinowozunifiz.pdfIn PDF document text
    • http://cafesezony.ru/fck_editor_files/files/71958684391.pdfIn PDF document text
    • https://ngaa.org.au/application/third_party/ckfinder/userfiles/files/46102440555.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/161449eaa1d4f9---paposaw.pdfIn PDF document text
    • https://www.cosanuesa.com/componentes/editor/ckfinder/userfiles/files/zuforatozukovub.pdfIn PDF document text
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/mevojiropuxajovaviwo.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/8751625923.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614162959aa6a---69586792377.pdfIn PDF document text
    • http://www.huntsvillepr.com/files/files/nulobe.pdfIn PDF document text
    • https://parvazyab.com/basefile/api203/files/83336149034.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=download+sehhaty+appPDF 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_off0000df31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF31 10496 bytes
SHA-256: 9e18485145eef2a2738e789a6888ddd9ee00998629ee2b92af003e13fd4237f4
font_01_sfnt_off0000f71b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF71B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F2D 18052 bytes
SHA-256: d4bfef6bf07ade87d83d006c509cb6fedbd83c3b0a24a20b5759cf3ef3b75896