Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1f72563305a110e…

MALICIOUS

PDF

75.5 KB Created: 2021-09-08 12:32:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a8c5f0ca6f2fe624124ac17b9ad9a1d1 SHA-1: ad5c98b6fc1faa49bfc4256f21faf878afba36c6 SHA-256: a1f72563305a110e320233a88a57845654d6ad8b4157108219d8cf86fb47d6fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs pointing to a variety of domains, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, specifically identified as phishing or a trojan. The structure suggests a link farm designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://drafthe.ru/uplcv?utm_term=kindergarten+composing+and+decomposing+numbers+worksheets PDF link annotation
    • http://burelomdo.com/ckfinder/userfiles/files/36038872747.pdfIn PDF document text
    • https://sibiucuratenie.ro/fckeditor/userfiles/file/57192033295.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/161378d8d0e197---pivituwaw.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/42533309115.pdfIn PDF document text
    • http://bike-aholic.com/UserFiles/file/ruletagov.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/14982793307.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/c48271e0868ac3cc1b89f9fcb5f97033/32532931410.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/88736047842.pdfIn PDF document text
    • http://strahyi.ru/images/file/wudumulu.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16137b1a3cf5d6---93533062412.pdfIn PDF document text
    • https://guclupin.com/calisma2/files/uploads/4638031641.pdfIn PDF document text
    • http://maidichike.com/upload/files/64407511416.pdfIn PDF document text
    • http://kprmk.pl/userfiles/file/45818796931.pdfIn PDF document text
    • http://restaurant-lyons.fr/userfiles/file/lematigokixusunexigalazep.pdfIn PDF document text
    • http://thecuriosityshot.com/vosexidurim.pdfIn PDF document text
    • https://suativisamsungtaihanoi.net/upload/files/1551882882.pdfIn PDF document text
    • http://www.plain-pied.com/editeur/ckfinder/userfiles/files/88309069669.pdfIn PDF document text
    • https://artesapanaderia.xyz/aym_image/files/3337254775.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/57457818942.pdfIn PDF document text
    • https://quangcaomattroi.com/uploads/news_file/43707481829.pdfIn PDF document text
    • http://franceplus.fr/userfiles/file/66582429819.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/10349635646.pdfIn PDF document text
    • http://ddservice-bmw.pl/userfiles/file/30277543097.pdfIn PDF document text
    • https://flomogroup.com/upload/files/22918124020.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_off0000c14a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC14A 11324 bytes
SHA-256: 3890d5aa9b89df045e98c1a262d8ce009af96a01743732a13c7d0539a9d2a5bc
font_01_sfnt_off0000db59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB59 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f36b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF36B 17172 bytes
SHA-256: 31850848008f758907349ca8a6758630ff1b2016e61fede61d6caf1a339f5456