Malicious PDF — malware analysis report

Static analysis result for SHA-256 0786fdc743875c86…

MALICIOUS

PDF

82.4 KB Created: 2021-09-10 07:49:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b908e268a141a507c99711051f3e7589 SHA-1: 12f3b61246e60791a46ce8748e78b8ebd95f9bf0 SHA-256: 0786fdc743875c86b0b405e5209a89c4b5313a4818b04f3c03001ef4ab6faf82
134 Risk Score

Malware Insights

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

The PDF contains numerous links to disposable hosting, with one specific URL disguised as a firmware update. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and a link farm heuristic further supports this, suggesting the document is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://inwebjor.ru/uplcv?utm_term=nexus+5x+firmware+update PDF link annotation
    • http://lngpetro.com/userfiles/file/6236900658.pdfIn PDF document text
    • https://grandegroup.net/files/1631930120.pdfIn PDF document text
    • http://www.rosabrockenhaus.ch/ckfinder/userfiles/files/1159834516.pdfIn PDF document text
    • http://makairways.in/home/makairways2017/public_html/dowalumniusa/ckfinder/userfiles/files/66023792444.pdfIn PDF document text
    • http://branonperformance.com/ckfinder/userfiles/files/54489139849.pdfIn PDF document text
    • http://burmeseburmilla-allevamento.com/userfiles/files/71039407663.pdfIn PDF document text
    • http://borneneskontor-landsforening.dk/userfiles/file/xivop.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/32393206989.pdfIn PDF document text
    • http://gat-asset.com/CKEdit/upload/files/gisorugadasimakidal.pdfIn PDF document text
    • http://fleshlight-tw.com/userfiles/file/ronudojezuxavavawa.pdfIn PDF document text
    • http://clinicaveterinariagussago.com/userfiles/files/pixufosifupilabetejab.pdfIn PDF document text
    • https://cornwallstaffagency.com/userfiles/file/76773098680.pdfIn PDF document text
    • http://runwellconsulting.eu/file/file/32876063888.pdfIn PDF document text
    • http://phutungtdc.com/upload/files/diwokafazibejorexofevi.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613804e84daef---61628130668.pdfIn PDF document text
    • http://22vek-omsk.ru/fck_editor_files/files/rikisipirafebisadofewole.pdfIn PDF document text
    • http://elskup.pl/images/assets/file/81768791006.pdfIn PDF document text
    • https://nobelboya.com/userfiles/file/72061791608.pdfIn PDF document text
    • http://billsky.ee/files/file/15274353691.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/2h8ccnu2edfo9escpjpmk6vm8m/10644145413.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/68499614108.pdfIn PDF document text
    • https://aluminiosarla.com/userfiles_arla/files/37735289120.pdfIn PDF document text
    • http://i-akparat.kz/ckfinder/userfiles/files/lunopareladadevetuwiper.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_off0000dca0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCA0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f4b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4B7 10788 bytes
SHA-256: e07cab13f20690a60f4193834484276c05867c12848a158f3c2aef27a1c4ca64
font_02_sfnt_off00010dbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DBB 17952 bytes
SHA-256: 98f2c181c01f1b865631f05d01db40d32236078753425f68dff8283c4716f5bc