Malicious PDF — malware analysis report

Static analysis result for SHA-256 8ef0df77c57ffbf4…

MALICIOUS

PDF

106.9 KB Created: 2021-07-08 01:09:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: d79ee6041cb87011fba6f7f2ac291f31 SHA-1: 5424024fb79068f80c30215ab0d3192a2384e6bb SHA-256: 8ef0df77c57ffbf4703f32900b3814e0b2e85705d3f9470990a73ad9b8e02214
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous distinct hosts, many of which are compromised WordPress installations. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded URLs are designed to lure users into clicking on them, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9780

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://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7271b685ff---90723524232.pdf In PDF document text
    • http://famcareconnect.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609b381792aa5---zibafuposajezesutekap.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608b1ffb5776d---94970238532.pdfIn PDF document text
    • http://aldara-latinoamerica.com/userfiles/file/94307144068.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/ripuzi.pdfIn PDF document text
    • https://cvenhancer.com/wp-content/plugins/super-forms/uploads/php/files/a9c5d7103d868153c05becadde0406a2/16870194719.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/gn1dpkj2jn8ea8m1rcr66eopd4/gifotuwabonojiwe.pdfIn PDF document text
    • https://ltgtrends.com/wp-content/plugins/super-forms/uploads/php/files/d5837dd98d2b9bbfa46040af6866a6c3/22112170238.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/3b445v8ihh9g1ip9hgu32h8ps1/sesaxulegekokamaj.pdfIn PDF document text
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/d39a59aa9b483a353eb8e6a6c46abb77/70887409828.pdfIn PDF document text
    • http://kutyasturak.hu/images/files/marinak.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/2498060370.pdfIn PDF document text
    • http://canadanur.com/resimler/files/jikotek.pdfIn PDF document text
    • http://prota.ru/upload/files/pukuxitolaxalerigolero.pdfIn PDF document text
    • https://israelonthehouse.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092a0c381ce3---peziziporalo.pdfIn PDF document text
    • http://industra.sk/userfiles/file/92683543332.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c737baa0102---77732737296.pdfIn PDF document text
    • https://batikatravels.com/userfiles/file/79002461577.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/q3gukvoikbhaiv53rutvgc2f66/loratasovebirosukakow.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16080cd787e3fd---25691524338.pdfIn PDF document text
    • http://www.victoriousintl.com/new/resource/files/guzadediwa.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/od121fmleuj3758sc57urn073f/61348246868.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091cc0b45f11---firixotituw.pdfIn PDF document text
    • http://automsystem.com/UploadFile/file/20210509070446861.pdfIn PDF document text
    • http://rhodeislandalpha.com/clients/56223/File/senuzugutubadufuj.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d522748c50---kunukarated.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607f0a1cf321d---71665284007.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=shadowlands+balance+druid+guidePDF 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_off00013d51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D51 17984 bytes
SHA-256: e327237f7b9494e4dc57f3e77cc1f5e555c0bfe25c43a086434073b5e2de41e4
font_01_sfnt_off00016cdd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16CDD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000184f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x184F4 10952 bytes
SHA-256: 3bb73c6a58f5baff40da5c7c15cb8891359f62b326eecc9a0f80b262bedd5d08