Malicious PDF — malware analysis report

Static analysis result for SHA-256 40b160127cc4bf87…

MALICIOUS

PDF

82.1 KB Created: 2021-09-17 07:53:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c8500bc22b993b038021daa6b01fce47 SHA-1: 7dd41b7c2e9ef12655935834ecc58deb6d9ad77b SHA-256: 40b160127cc4bf87398c8d00a946c426cda6a925e824af90dbcf06e2380e4819
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the high ML score strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the nature of the URLs and the ClamAV detection point towards a phishing or trojan delivery mechanism.

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
  • 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://huntic.ru/uplcv?utm_term=super+pixel+heroes+mod+apk PDF link annotation
    • http://rrarental.org/upload/file/sebalub.pdfIn PDF document text
    • https://bosingels.nl/ckfinder/userfiles/files/20964385677.pdfIn PDF document text
    • https://ph2020.org/FCKeditor/file/mabijolekapisexilisanuge.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/fepevonajotapaduwekegut.pdfIn PDF document text
    • http://geombiagioschettino.eu/userfiles/files/14520759344.pdfIn PDF document text
    • http://skoleniridicu-online.eu/ckfinder/userfiles/files/40482086186.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/161328bdfe0f8e---93380081882.pdfIn PDF document text
    • http://sutipatika.hu/userfiles/files/logokasasawininami.pdfIn PDF document text
    • http://kemnhapkhau.com/upload/files/80343720802.pdfIn PDF document text
    • https://detmers-kontejner.hr/files/kekedap.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/xanutop.pdfIn PDF document text
    • http://www.siposferenc.hu/html/nukagovigudojiruxo.pdfIn PDF document text
    • http://tjsijiqing.com/ckfinder/userfiles/files/2021/0912/6b4f2c551068d008d8610c776500e665.pdfIn PDF document text
    • https://vinaarc.com/app/webroot/files/ckfinder/userfiles/files/keluzezeda.pdfIn PDF document text
    • http://net-work.cz/data/file/daxojitere.pdfIn PDF document text
    • https://kimansion.com/uploads/file/72767565126.pdfIn PDF document text
    • http://cbgnfinance.com/userfiles/file/joginamodokonodolur.pdfIn PDF document text
    • https://avflash.nl/upload/files/sosoxemafonivilibegi.pdfIn PDF document text
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/4b82a6ae2c282ea7af95e9687c1b9cb1/2920671329.pdfIn PDF document text
    • http://levakov132.ru/userfiles/file/jaruguji.pdfIn PDF document text
    • https://medicabg.com/uploads/wysiwyg/files/89323066714.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/7j6anjhk58f3e52ps3osta3321/7536254227.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/16139ebb433656---3728539336.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_off0000da1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f234.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF234 10824 bytes
SHA-256: c321829321dff5cda3832c680c72e2222f5f9442ba8f4d60901cca026e5a75ac
font_02_sfnt_off00010b15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B15 18488 bytes
SHA-256: e6bc70bc905ce4ecdbfa0c2609875b177652ab64f0dd3b7f4c8f5c834b7dec2b