Malicious PDF — malware analysis report

Static analysis result for SHA-256 b104559112d02c83…

MALICIOUS

PDF

68.7 KB Created: 2021-09-27 17:04:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: c8b2804f89f3d65994f5eca60cfed0cd SHA-1: 2859dfc541fcc2e2af5ba6e703c8cac180d5bc81 SHA-256: b104559112d02c835867136889ea11210b50ed7281bf07da2c1dfd099fd469f5
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF is identified as a phishing lure due to its small size and image-heavy content, typical of a screenshot designed to hide a clickable action. Multiple heuristics, including ML classification and ClamAV detection, confirm its malicious nature. The document contains numerous embedded URLs, many of which point to disposable domains, suggesting a campaign to distribute malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://clubelsendero.com/img_pag/file/zinewanofitojewofidobedil.pdf In PDF document text
    • http://nikolabartakova.cz/files/file/50070774260.pdfIn PDF document text
    • http://gocreate.termall.pl/upload/fck/file/88213093476.pdfIn PDF document text
    • http://customize.fr/fckeditor/editor/filemanager/connectors/php/img/Editor/file/55156828906.pdfIn PDF document text
    • http://homeloanz.net/images/e/file/xegomaposuworakinab.pdfIn PDF document text
    • http://zhongguohuachun.com/d/files/vowefinutuxanazu.pdfIn PDF document text
    • https://encoyun.com/calisma2/files/uploads/46074448988.pdfIn PDF document text
    • http://minerva-collection.net/files/files/suxazagesozasufadubegi.pdfIn PDF document text
    • http://loaamtran.com/files/usersfiles/files/2806963775.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/29611258377.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/4ae86a816582c774910af987278e2633/xakawupagevow.pdfIn PDF document text
    • http://www.aamuhsv-madisonalumni.org/files/files/bujaduditotibu.pdfIn PDF document text
    • http://olivetheater.com/userData/board/file/negakevajekeropefebe.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/37078886398.pdfIn PDF document text
    • http://emekyesiltepe.net/images_upload/files/47382152937.pdfIn PDF document text
    • http://www.prctech-th.com/ckfinder/userfiles/files/radibasumavebolopobisek.pdfIn PDF document text
    • http://sun-green.de/ckfinder/userfiles/files/limawamolubup.pdfIn PDF document text
    • https://georeno.ca/userfiles/files/bimisusafa.pdfIn PDF document text
    • http://vinhthuan.com/upload/files/bogilomifasifovasa.pdfIn PDF document text
    • http://519pf.com/userfiles/files/89720701784.pdfIn PDF document text
    • https://vadihosting.com/calisma2/files/uploads/bipatibopazum.pdfIn PDF document text
    • https://inprovitbolivia.com/ckfinder/userfiles/files/48524513444.pdfIn PDF document text
    • https://isuzuphonoi.com/data/dulieu/files/jufojuzoxaxaro.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=battle+cats+hacked+version+downloadPDF 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_off0000b093.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB093 14272 bytes
SHA-256: a612a5ded746272f465b23594cf1c8e1c07348eaa0e3fe73cae21fa7ca655e9a
font_01_sfnt_off0000d428.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD428 10764 bytes
SHA-256: 8df98bd0d84a92cb7f4d16790b33b69da7d21f2047e55e0b3804522b323efda1
font_02_sfnt_off0000ecf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECF6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1