Malicious PDF — malware analysis report

Static analysis result for SHA-256 f77b4f173a82d06a…

MALICIOUS

PDF

87.2 KB Created: 2021-09-21 01:00:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: dfa9dfcde75c258ad138df6eb23db9c6 SHA-1: 60972e91f011bcae9144b24a00e6602617fad5dd SHA-256: f77b4f173a82d06a804f12cd5313fb5d130cc44efbf8ae1639c9cfae5601c334
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to disposable hosting, indicative of a phishing or link farm operation. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically identified as a phishing trojan. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards the exploitation of PDF vulnerabilities or social engineering to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://allytemp.ru/uplcv?utm_term=william+shakespeare+much+ado+about+nothing+pdf PDF link annotation
    • https://myshalewell.com/userfiles/file/97648792355.pdfIn PDF document text
    • http://re-media.ru/foto/ck/files/korufebodigesofok.pdfIn PDF document text
    • http://www.mearesandassociatesllc.com/siteuploads/editorimg/file/5779838532.pdfIn PDF document text
    • https://podimercrm.com/img/files/bejarofob.pdfIn PDF document text
    • http://atmaircenter.com/lb/userfiles/files/xugimo.pdfIn PDF document text
    • http://lammermoor.net/imagenes/file/zerolafak.pdfIn PDF document text
    • https://cnc-ar.ro/files/file/24686927548.pdfIn PDF document text
    • https://vhcvietnam.vn/ckeditor/images/files/nagiwix.pdfIn PDF document text
    • http://www.urbanwaterways.info/files/58249277855.pdfIn PDF document text
    • https://dialogueinpraxis.net/files/docs/zogitodejub.pdfIn PDF document text
    • http://xn--80aiddhbkcq5bcaz.xn--p1ai/upload/files/nazogima.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/zudosazumotulosijap.pdfIn PDF document text
    • http://sinsg.com/files/fckeditor/file/28253116835.pdfIn PDF document text
    • http://posicert.com/upload_fck/file/2021-9-12/20210912011529817074.pdfIn PDF document text
    • http://vitalchurchesinstitute.com/files/file/kidufuxapodamowo.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/d0649e7a585debcdcdd161ac5f415b6e/medesikewarumolowegewu.pdfIn PDF document text
    • http://ensky-chemical.com/upload/files/nupiluwanixopovatus.pdfIn PDF document text
    • http://mprime.net/ckfinder/userfiles/files/kujuv.pdfIn PDF document text
    • https://zoomkish.com/basefile/zoomkishcom/files/mujigip.pdfIn PDF document text
    • https://2winit.com/Files/files/xeteritojukunimexepug.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613f88ebb3c47---firulurowurazavomapa.pdfIn PDF document text
    • https://excellencetogether.com/img/files/file/18219556202.pdfIn PDF document text
    • http://floramarble.com/uploads/65946022094.pdfIn PDF document text
    • http://showdoimovel.com/files/files/tapusebixixulutalosixiv.pdfIn PDF document text
    • https://kasihpaham.com/contents/files/tonelodufuf.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d411.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD411 17596 bytes
SHA-256: d7874bb3a76441231376f8d3830044d4f14cada599820d7c0f6f00da258f062d
font_01_sfnt_off0000ee86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE86 17516 bytes
SHA-256: ec99b28484ec29bba7b33f1b5d782d0e99932d9c7f9c31c3f6f7c91302460dfb
font_02_sfnt_off00011c01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C01 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00013418.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13418 11392 bytes
SHA-256: c59259f8f344a11b4b434881d7dd537427bce58da18bf8e65cc23f51935ad965