Malicious PDF — malware analysis report

Static analysis result for SHA-256 215ea91dad3d5c69…

MALICIOUS

PDF

81.1 KB Created: 2021-09-16 15:07:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fe2ec5f0445bc4fddbf3f15c74060ab9 SHA-1: 4eb92845e2bf69c84f428314b6f3314d2a558a99 SHA-256: 215ea91dad3d5c6954387d2a2f2b81762f040ee157c287b6ad09bca9ec428836
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload directories. This structure is indicative of a link farm designed to host malicious content or redirect users to phishing sites. The ML classifier and ClamAV detection strongly support its malicious nature, classifying it as a phishing or trojan threat.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://namngonviet.vn/user-/files/jefejiw.pdf In PDF document text
    • https://sf-tfi-pgu.uz/wp-content/plugins/super-forms/uploads/php/files/54f9e661f7e4e25c5fe7c047b7c4d00e/tumipizajabuxudivewewivin.pdfIn PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/tinenalewute.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/bdf0489d78e847b4d7852451b43febe8/zufevujam.pdfIn PDF document text
    • http://kaizenlife.com/ckfinder/userfiles/files/35452012291.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/78622074785.pdfIn PDF document text
    • http://lmleadmanagement.com/userfiles/files/53456017322.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef2db8cc31---26652099571.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136035926346---tijagego.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/96557838830.pdfIn PDF document text
    • http://birzebbugastpetersfc.com/files/file/50874059419.pdfIn PDF document text
    • http://iiiemjobs.com/FCK_Editor_Images/files/71517581203.pdfIn PDF document text
    • http://peter-scherer.de/userfiles/file/28181624555.pdfIn PDF document text
    • https://edu-mate.kr/_UploadFile/Images/file/gedafuluxazix.pdfIn PDF document text
    • https://neksav.com/upload/ckfinder/files/dorumu.pdfIn PDF document text
    • http://dison.cn/filespath/files/20210913140405.pdfIn PDF document text
    • http://sun-green.be/ckfinder/userfiles/files/15543098019.pdfIn PDF document text
    • http://humanlitech.com/files/files/2262435610.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/7b38c1158f97a287bd4306dc970d45e2/dewibozesajakokit.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/57481185303.pdfIn PDF document text
    • https://ladangmimpi.com/contents/files/40922518479.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/jojomulagodi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=pokemon+go+ios+10PDF 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_off0000d7db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7DB 10312 bytes
SHA-256: 12e5e227a68defc7344e906aefea706e8fbc5394496bc252e10de432ceca2dad
font_01_sfnt_off0000ef1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF1F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010731.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10731 18404 bytes
SHA-256: 49ce83711d5bab93f34f0e0abb673281e90b9fccd1f25b3967ffb9e29c796c39