Malicious PDF — malware analysis report

Static analysis result for SHA-256 44fe4e4da0416e98…

MALICIOUS

PDF

82.2 KB Created: 2021-10-13 14:13:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3c3c071377369dbbdc9f7c2cf30bec3a SHA-1: d8dd7b42975f206cc24903a50ccfd17447e1277b SHA-256: 44fe4e4da0416e989f60c3950ff2c39905867924ec5aa2648fde1fe5a0f69df0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to numerous external URLs, with several hosted on compromised WordPress upload directories. The primary purpose appears to be directing users to potentially malicious content through a deceptive link structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://kirbas.com/img/uploaded/file/xuzekele.pdf In PDF document text
    • https://healthlantern.com/ckeditor/ckfinder/userfiles/files/54915639951.pdfIn PDF document text
    • http://purepassion.pl/userfiles/file/19558997828.pdfIn PDF document text
    • http://iranjobex.com/cache/fck_files/file/kipajuxevapafavo.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210918_193405.pdfIn PDF document text
    • http://personal.sut.ac.th/chantira/port/ckfinder/userfiles/files/85466251591.pdfIn PDF document text
    • http://lyzebrno.cz/userfiles/file/wuxizukepebiti.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/bitotolam.pdfIn PDF document text
    • https://www.theknowledgeonline.com/files/lib/ckfinder/userfiles/files/8361192918.pdfIn PDF document text
    • https://wecareu.net/ckfinder/userfiles/files/risotirugarem.pdfIn PDF document text
    • https://itchanoi.vn/uploads/news_file/jotebawij.pdfIn PDF document text
    • https://tiemhoahaibara.com/data/dulieu/files/nuzadepimoma.pdfIn PDF document text
    • http://duet-czluchow.pl/userfiles/file/zamaxutujopofe.pdfIn PDF document text
    • http://zawodydrwali.pl/app/webroot/userfiles/file/97901662968.pdfIn PDF document text
    • http://sasolution.kr/userfiles/file/4198116919.pdfIn PDF document text
    • https://www.landalastadservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c4c7daba48---87641702400.pdfIn PDF document text
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/ae2e748d38b50c0efc328fcc77ae33c3/tijidadovewigaxotaxo.pdfIn PDF document text
    • https://growmytruck.com/wp-content/plugins/super-forms/uploads/php/files/d8e16b02dd3dc3fd2833dd220d420210/71057505922.pdfIn PDF document text
    • http://pneusmarene.it/images/file/36956818605.pdfIn PDF document text
    • http://rentaruedas.com/files/others/24333248197.pdfIn PDF document text
    • http://kenhuffbuilders.com/userfiles/file/jafosogizumigizakud.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/a6j0jfbpi9fnsltidv2e0kq1pa/66628982076.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/BcFPVxLj4jw/uplcv?utm_term=they+complement+each+otherPDF 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_off0000da98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA98 10456 bytes
SHA-256: 589fffb73bb38e0518ee12112016e234b902885a01eb6f40fa07e1f694437843
font_01_sfnt_off0000f231.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF231 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A43 19364 bytes
SHA-256: 411856c4edb64ec16c16beaaa2cc828dc0bb2e28401ba475f6cf3099e65a0668