Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb473ad435b3f7b5…

MALICIOUS

PDF

80.7 KB Created: 2021-09-10 20:24:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 2f9cef9112f42893f70716f1670ff48f SHA-1: 53e5329e3d509eda0d74a0f53eec5f123ad9d213 SHA-256: cb473ad435b3f7b5d8e7b8f0a798ffebde3e1c2a5d0aaf7f68f2baa174795ba9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laborke.ru/uplcv?utm_term=cloudflare+warp+apk PDF link annotation
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161327221181b6---56160139764.pdfIn PDF document text
    • https://akanaymatbaa.com/calisma2/files/uploads/rosolugamolele.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/c3d8bcf4ecfede1f060819cb96eccbaa/gupunos.pdfIn PDF document text
    • https://4cmedica.com/ficheiros_upload/file/60915452450.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/dexoliboka.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/lawaxebuwulaluwepe.pdfIn PDF document text
    • http://tradotel-riviera.com/file/1859742657.pdfIn PDF document text
    • http://daltan.hu/userfiles/file/todejafetew.pdfIn PDF document text
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/22368840377.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613334d962bf4---fetidogegadepetunib.pdfIn PDF document text
    • http://klawiatury-foliowe.pl/_data/file/buluxinutogopiladad.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/61635542579.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613785ea5d8de---64556036910.pdfIn PDF document text
    • http://mauchlineware.com/html/chapelstreet/web/userfiles/files/wedaloxewexedujupekimu.pdfIn PDF document text
    • http://solarexperten.ch/fckeditor/editor/images/file/lilodo.pdfIn PDF document text
    • http://riasztoszolnok.hu/admin/fck_upload/file/36465439223.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b67d79b20f---67202640393.pdfIn PDF document text
    • http://travelport.pl/userfiles/file/jatij.pdfIn PDF document text
    • http://xn--h1acbpobggs.xn--p1ai/data/files/pibekofofu.pdfIn PDF document text
    • http://futuralagoparking.eu/userfiles/files/nunedokuvivijijedud.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/16134d1afbe191---76163392073.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_off0000d546.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD546 10340 bytes
SHA-256: d9f52fb48246f7af2781d3106b80c9636785c841d6687cb14477f216eb8c29cc
font_01_sfnt_off0000ecd7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104e9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E9 18660 bytes
SHA-256: b17f8c23eb4fbbad3f42e25403af752373e7a6745fbf07395e5d88f4f59890f2