Malicious PDF — malware analysis report

Static analysis result for SHA-256 943cdf8cb196dfd4…

MALICIOUS

PDF

69.1 KB Created: 2021-09-24 14:35:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: b004fed0aa7f19c8b7a9516ad856b5e5 SHA-1: 3ca1fbe064ced126f99b3bc5cc368610da94d3c2 SHA-256: 943cdf8cb196dfd48a2c36731a43673807eb7799295c5c87253ef03a6579d139
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. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites and disposable hosting. These links likely serve to redirect users to phishing pages or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

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://irlanc.ru/uplcv?utm_term=android+xxx+video PDF link annotation
    • https://villamishkan.com/310renonew/front/images/files/gixebujesonoraz.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/161460a371443d---noluz.pdfIn PDF document text
    • http://baove24h.org/upload/files/78749735106.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16147af4086a95---xopuratemox.pdfIn PDF document text
    • https://www.leadercaravans.com.au/application/third_party/ckfinder/userfiles/files/xafigaviredu.pdfIn PDF document text
    • http://bn-biz.com/userData/board/file/83354138026.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/96592005501.pdfIn PDF document text
    • https://vjlabor.pitscovn.com/uploads/Upload/files/fibamovopoxujatozukeba.pdfIn PDF document text
    • http://miyozenemeryville.com/uploads/files/ganofebu.pdfIn PDF document text
    • https://etevent.itweald.com/uploads/files/61458ebf1dd76.pdfIn PDF document text
    • https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/6f013a13a09d3610a09067a2699ef472/tuxutokog.pdfIn PDF document text
    • http://china-steamboiler.com/d/files/81008131898.pdfIn PDF document text
    • http://tjjjsh.com/uploads/files/83169777970.pdfIn PDF document text
    • http://terralis.net/catalogue_dynamique/file/buxirefimowo.pdfIn PDF document text
    • https://branchennachweis.eu/userfiles/file/44849089577.pdfIn PDF document text
    • http://skybuildinfraprojects.com/uploads/20653818464.pdfIn PDF document text
    • http://wawabed.pl/uploads/userfiles/file/kozofezawimi.pdfIn PDF document text
    • https://pellevah.com/upload/files/61189214618.pdfIn PDF document text
    • http://ombs.ru/uploads/files/77163117836.pdfIn PDF document text
    • http://erh-hu.com/userfiles/file/jewavikedukexanomekorava.pdfIn PDF document text
    • http://xn--vb0b83rba554gca.kr/page_data/file/20210913220124.pdfIn PDF document text
    • https://mashura.co/userfiles/files/nobudisejulobosomegikun.pdfIn PDF document text
    • https://autoteam.in/ckfinder/userfiles/files/47888541417.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://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_off0000b260.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB260 9916 bytes
SHA-256: dd42b5581d15ada6e44338828718b0630b461bedd93ee8a22cbff71c57767813
font_01_sfnt_off0000c858.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC858 16392 bytes
SHA-256: 7442ea03a37b8d580a06a2320b961d912d608d60a63f4677c56df30c78b39b48
font_02_sfnt_off0000f241.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF241 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1