Malicious PDF — malware analysis report

Static analysis result for SHA-256 85769628bf5bb77b…

MALICIOUS

PDF

74.8 KB Created: 2021-09-12 19:49:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 234085ee3f7f3090a13ae3e6103d15f6 SHA-1: d12019904eafbdc8368d62bfe8554d030cad8076 SHA-256: 85769628bf5bb77b1fd8778687d883ff441dffb0ff7c2adb181cc05aa639946e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. It contains numerous external URIs, with one specifically pointing to 'irlanc.ru' and a query parameter suggesting a lure related to retrieving deleted messages. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further suggests a link farm on disposable hosting, reinforcing the phishing or malware distribution vector. No scripts were extracted, but the presence of external links is the primary indicator of its malicious function.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://irlanc.ru/uplcv?utm_term=retrieving+deleted+whatsapp+messages+on+android PDF link annotation
    • http://trufeel.com/ckeditor/ckfinder/uploadfile/files/buwikosipudoza.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ebfda7cda---82687701620.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/geweduwavomupilomiditex.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/nonadovamonemukadowibu.pdfIn PDF document text
    • http://naturpix.ch/cmsimages/file/bowofi.pdfIn PDF document text
    • https://philly.drinkpoint.com/uploads/files/jawidodukerepumakezitova.pdfIn PDF document text
    • http://hooleihomes.com/cms_images/file/kikanelesola.pdfIn PDF document text
    • https://thehouseconcert.com/ckfinder/userfiles/files/16151455993.pdfIn PDF document text
    • http://ebsenglish.net/_UploadFile/Images/file/lujulapizonixugimi.pdfIn PDF document text
    • http://www.southforconstruction.com/frontend/web/ckfinder/userfiles/files/zolado.pdfIn PDF document text
    • http://www.corazondelsol.es/ckfinder/userfiles/files/resaguzegu.pdfIn PDF document text
    • https://www.puskinas.lt/ckfinder/userfiles/files/gavalaruvepaputosaton.pdfIn PDF document text
    • https://ehotelgateway.com/bot/ckfinder/uf/files/65304379829.pdfIn PDF document text
    • http://kiddeefire.com/media/userfiles/files/nirewovuxagis.pdfIn PDF document text
    • http://bscsaoner.in/ckfinder/userfiles/files/95756879007.pdfIn PDF document text
    • http://yongqingtech.com/d/files/5219646763.pdfIn PDF document text
    • http://dungcubepgiangtrinh.com/webroot/img/files/85971390797.pdfIn PDF document text
    • http://vietsaovang.com/uploads/userfiles/file/14320940878.pdfIn PDF document text
    • http://otpetye.com/images/shared/file/86378281340.pdfIn PDF document text
    • http://muasamhangmy.com/ckfinder/userfiles/files/63147056231.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161305049af605---detegizodeseruvo.pdfIn PDF document text
    • http://dragoniresorts.com/userfiles/liviwerejojo.pdfIn PDF document text
    • http://e1pl2.nazwa.pl/busy/fotki/file/bokakaduv.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c12f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC12F 16756 bytes
SHA-256: 0c2501090e4f5c12aaeaa165b2eee90a315f88e8ddf5e71093b84660aa4bfbf6
font_01_sfnt_off0000ebfd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBFD 11036 bytes
SHA-256: a3138d505785dad47449352079ba3dc75d691ae0fbcdb1d3e01c0abb5c838924
font_02_sfnt_off00010558.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10558 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1