Malicious PDF — malware analysis report

Static analysis result for SHA-256 a0f4af923a556abf…

MALICIOUS

PDF

75.1 KB Created: 2021-06-11 18:58:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f20b6c0f2f8b1196622486b576fa0770 SHA-1: 698539b26d2646fa298e29715c6528e3a7a63bf4 SHA-256: a0f4af923a556abf22b03e26203c1f1fc5136ce578387c29b7c617c5cb43e95a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains a link farm pointing to numerous URLs, many hosted on compromised WordPress sites, suggesting a phishing or malware distribution campaign. The presence of external URIs and the nature of the link farm indicate an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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
  • 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://smidgel.ru/uplcv?utm_term=ielts+writing+task+2+band+5+sample PDF link annotation
    • http://firmykominkowe.pl/Obrazki/edytor/file/50911357593.pdfIn PDF document text
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/s4a1nqqna1uq3tb1flo3703n35/xubuwuzawutupiwaza.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079288a65228---fomat.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/c161929e31175f79e9758b470f37a8c2/62560881260.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb2dd0242d7---povowujulikezizurojipovas.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/wumowaderegox.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f7161a6b40---68724343152.pdfIn PDF document text
    • https://mfdesign.hu/files/file/muxinoxari.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/d4oia60rm6ran8v7k07iqee6b7/jomugixofi.pdfIn PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/918f92b9a534867fdfc1a97845c43c22/59795019345.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/7357ihta3mvgm62b1kjbl2fihs/likilemuxemal.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-5-17/20210517115635801464.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609763f873ff6---titasunawiluxekififema.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/5fa502d1f99135e1dc66c363fee75c24/muvaxoneb.pdfIn PDF document text
    • http://xn--or3bi2da319p.com/upload/fckeditor/file/tiginoxujunutadotipeg.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/da79cbde1bc0a485c8b7bd52e8393959/xipazazusebuguz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e613.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE613 5768 bytes
SHA-256: a3e8311b0b0ad86f916ebbccc4b3f17ab34f772ab88c3b4d785b36140c9d0a6f
font_01_sfnt_off0000f9b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B4 11084 bytes
SHA-256: e2ac27a27c827625fd805f3b578602010b944e664b40685fab44fb85c7c453b5