Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb14b9bab646b913…

MALICIOUS

PDF

92.2 KB Created: 2021-06-25 13:02:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: fbbd688445f3c817d4d81bd7fe9e1688 SHA-1: 19713b8dead81d0d1f4499727f0a72384e68999b SHA-256: fb14b9bab646b913bfb8047721417ed336b8e457eb2c727e1915fe4535ed7995
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains numerous links to external websites, many hosted on compromised WordPress installations or disposable domains, suggesting a link farm or redirection scheme. The presence of embedded URLs and the nature of the heuristics indicate the file's primary purpose is to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://philabc.ru/uplcv?utm_term=bird+with+most+beautiful+song PDF link annotation
    • http://shsuorui.com/uploadfiles/fckeditor/20210623/file/16244449936901.pdfIn PDF document text
    • http://martonaroniskola.net/userfiles/file/vebapimunulijakufufumaka.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608f295d1b97c---javidejitekoneponu.pdfIn PDF document text
    • https://hgb.se/filer/file/sovezi.pdfIn PDF document text
    • http://adanateknikservis.web.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c98420acc3---kiguraruzagilo.pdfIn PDF document text
    • https://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/f088eb69f4f6649a26ce8494898d865b/fijizituta.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/3f7cc87de5ae4bee35a380e6bff7bda5/934245468.pdfIn PDF document text
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/160b7673c227de---67162301215.pdfIn PDF document text
    • http://coffee33.ru/archive/file/sekagiwevegojiba.pdfIn PDF document text
    • http://sherwoodchambergolf.com/ckfinder/userfiles/files/tuluguxireruwojuw.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/49857361111.pdfIn PDF document text
    • https://opuntia.eu/wp-content/plugins/super-forms/uploads/php/files/fdc9daf6d8ac761b30092ca3a993928d/85454333818.pdfIn PDF document text
    • http://nuyewpilot.academy/wp-content/plugins/super-forms/uploads/php/files/a3f0bdd37331c61e5042aa66d0be5418/fipokaditiwunogonapuviz.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606e478920647---76554422939.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/439d145b533cc1f256641336479f91e6/kevenabatodefiko.pdfIn PDF document text
    • http://ctkupavna.ru/upload/file/16823121932.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_off00010509.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10509 17196 bytes
SHA-256: 2f5ba0ed48412627eabd42c7cb6d5bfe790bf0478a0886c8c140a1a8e2854fb2
font_01_sfnt_off00013233.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13233 11180 bytes
SHA-256: fd9e25677fae84253b78aef2107b41e63d9a30d6ed2a8883a818dd788bd5ab84
font_02_sfnt_off00014c08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14C08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1