Malicious PDF — malware analysis report

Static analysis result for SHA-256 872a37c34b27a624…

MALICIOUS

PDF

80.9 KB Created: 2021-09-19 08:53:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ebb1aefc168757a24a476e5c5ed82098 SHA-1: 63fb472d953cc04d3bfd925360bab7bc577b7bb8 SHA-256: 872a37c34b27a6248937622b5c8066b24fcaf8dd9a32f7466d2954262be512bb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various domains, many of which appear to be compromised or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://huntic.ru/uplcv?utm_term=365+days+watch+online+free+123
    • https://luatsuavina.com/userfiles/file/46114945809.pdf
    • http://memsports.com.br/admin/libs/ckeditor/ckfinder/files/jigewifiwesawepot.pdf
    • https://divorcioconsensual.com.br/wp-content/plugins/super-forms/uploads/php/files/2d37efdba51458a5cc9d2cb5e233fc19/22132190228.pdf
    • http://ksiclub.org/projects/achievemore/admin/upload/fckImages/file/46085768251.pdf
    • https://abyway.lv/images/ck_images/files/6285088037.pdf
    • http://gro-felix.si/uploads/21084706273.pdf
    • https://ceccargiurgiu.ro/userfiles/file/mefewazofitenevu.pdf
    • https://cornwallstaffagency.com/userfiles/file/fuzuniv.pdf
    • http://savoie-outils-coupants.com/ckfinder/userfiles/files/zubunadutidoro.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131021a3b5a7---55341344057.pdf
    • https://estatecambodia.com/htdocs/cljr/data/files/bafifa.pdf
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614576ad3b35f---wubamonigojugufe.pdf
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16136f62120fb6---9129009694.pdf
    • http://ural-resyrs.ru/data/file/16000809686.pdf
    • http://www.detskaoptika.cz/ckfinder/userfiles/files/wojenubisar.pdf
    • http://www.brickchamber.com/ckfinder/userfiles/files/60489487894.pdf
    • http://shamayachts.com/upload/file/jovotalinexurabowin.pdf
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/f0fd17f5195acb9877ab773a6012b946/rozefitaxuvar.pdf
    • http://driver-jazda.pl/upload/file/48142777925.pdf
    • https://villadorottya.hu/uploads/frontend/files/22784635640.pdf
    • http://lesen-und-schenken.de/userfiles/files/28112270680.pdf
    • http://lacasedescaraibes.fr/file/ranefunedidesupop.pdf
    • https://ratodua.com/contents/files/26536287784.pdf
    • https://amezdigital.com/wp-content/plugins/super-forms/uploads/php/files/233a838fab525fdea1a301a9a2f9da63/9932612354.pdf
    • http://dkstores.gr/userfiles/file/disop.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d4cc.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4CC 16792 bytes
font_01_sfnt_off0000ece3.bin
a3abcdd80c4344cc123f5dbcbf3d09caf60e8c28342d6c7d9a793ebc70c04519
pdf-font-stream PDF embedded font (sfnt) at offset 0xECE3 11324 bytes
font_02_sfnt_off0001079a.bin
f6e4826d6eb2cc4020fcf80dc6d82302690ed82c13256de0e8f5e5803de3e297
pdf-font-stream PDF embedded font (sfnt) at offset 0x1079A 17612 bytes