Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5232f1119797162…

MALICIOUS

PDF

70.2 KB Created: 2021-10-11 04:32:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 2dcb792a780bc73c1159f7519329a765 SHA-1: 590419328af99d909ff669b2836d1214df131ca6 SHA-256: f5232f1119797162045ac97897737ba34939775e03cff92296fa55d2911b5db0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and numerous external links point towards an attempt to direct users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://helices-evra.com/userfiles/file/bojigilo.pdf In PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/4500043084.pdfIn PDF document text
    • http://mobilenmr.com/files/files/10369133747.pdfIn PDF document text
    • https://www.hotel-restaurant-plainfaing.fr/ckfinder/userfiles/files/tafufoxutu.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/95065418815.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109021833039738.pdfIn PDF document text
    • http://svatba-emi.com/uploads/pages/files/fezulelivoku.pdfIn PDF document text
    • http://sumosushingrill.com/uploads/files/64216318505.pdfIn PDF document text
    • http://xn----0tbbbfo0f.xn--p1ai/userfiles/file/48694868243.pdfIn PDF document text
    • http://synergyproperty.com/images/files/zurojivugukumuze.pdfIn PDF document text
    • http://pedraferro.com/files/files/94520543989.pdfIn PDF document text
    • http://dolphinkorea.com/files/files/mukedonifavexezererakut.pdfIn PDF document text
    • https://evabizz.com/userfiles/file/75814075183.pdfIn PDF document text
    • https://pustelnik-budownictwo.pl/ckfinder/userfiles/files/mexapazowogivazozemuxev.pdfIn PDF document text
    • http://studiotecnicoarduini.eu/userfiles/files/46065189968.pdfIn PDF document text
    • http://zanethompson.com/userfiles/file/21338463029.pdfIn PDF document text
    • http://phuketdriveschool.com/userfiles/file/66058600665.pdfIn PDF document text
    • http://ecole-belair.com/ecole/file/85117791315.pdfIn PDF document text
    • http://c2ctrading.org/cms_upload/files/kunozij.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/fepomopubim.pdfIn PDF document text
    • http://regimhotelierbucuresti.com/images/userfiles/wexivumuxunuzabo.pdfIn PDF document text
    • https://atasuorganiktarim.com/upload/ckfinder/files/vegux.pdfIn PDF document text
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1615e5d341f073---56451174185.pdfIn PDF document text
    • https://bfull.ru/uploads/files/43805187415.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=factors+affecting+the+growth+of+small+and+medium+enterprises+pdfPDF link annotation
    • 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_off0000b970.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB970 11228 bytes
SHA-256: e242bc0cdbc178402117e7a4e1e87aad184acb1af8c9f3d4ee789e9006189e3c
font_01_sfnt_off0000d367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD367 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB79 15224 bytes
SHA-256: c957dd9659bb020dc5a4b814da84d9e2e506bb8f6983c0a54ec9e2abf7ebb7a9