Malicious PDF — malware analysis report

Static analysis result for SHA-256 09b7aa9410c21f1e…

MALICIOUS

PDF

77.3 KB Created: 2021-09-09 04:49:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ed9f2a921438d3cf1cd18531f99cce5f SHA-1: 851f933789b38919d12811c9f8d2de6591a0a334 SHA-256: 09b7aa9410c21f1eb4b6391fc7da23401133c603b14310820b74c194674adba9
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised or disposable domains, likely for phishing or SEO abuse. The presence of external URIs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest a campaign to drive traffic to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://gberwanda.com/gbe/useruploads/blogs/files/rajolaxutukixamoxerateg.pdf In PDF document text
    • http://barbusci.it/maisUserFile/file/34966843301.pdfIn PDF document text
    • http://55pluscommunityspecialist.com/userfiles/files/2205680620.pdfIn PDF document text
    • https://digireg.li/upload/lazimoduj.pdfIn PDF document text
    • https://felicityokolo.com/file/gutoba.pdfIn PDF document text
    • https://vinniescustoms.com/userfiles/files/bupopalatunedazodiz.pdfIn PDF document text
    • http://boracayg.com/FileData/ckfinder/files/20210905_209CECA21FC4E6E2.pdfIn PDF document text
    • https://treasurehunterdetectors.solar-ovens.net/ckfinder/userfiles/files/podipalevanapepemir.pdfIn PDF document text
    • http://uniquehotelsolutions.com/files/others/36762950757.pdfIn PDF document text
    • http://pol2-simf.ru/userfiles/file/poxaga.pdfIn PDF document text
    • http://pedraferro.com/files/files/runulagodawapevudurofana.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/vuviveralefixegobitiduxub.pdfIn PDF document text
    • https://smgbid.com/ckfinder_userfiles/files/zumedi.pdfIn PDF document text
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/gurisofifo.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c39875d1f---61597823220.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/desenarivarivufa.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/vbuth5tgj3e37v8dafp4l7ifvq/nufaroli.pdfIn PDF document text
    • https://yourdentist.ro/app/webroot/files/userfiles/files/85609711945.pdfIn PDF document text
    • http://xindeshiye.com/uploadfile/file///2021090318415728.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files/luxurozodemajan.pdfIn PDF document text
    • http://sinostandards.net/upload/files/wenafajakewetuxego.pdfIn PDF document text
    • http://primeasset.hu/fileok/file/92791899986.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=solve+for+x+and+y+simultaneously+calculatorPDF link annotation
    • 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_off0000c812.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC812 17900 bytes
SHA-256: 590e434b13d0b62f5bc636e3e163ebe02ed24a086ad7ab3bbf47a8082af90f8f
font_01_sfnt_off0000f60e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF60E 11096 bytes
SHA-256: 2a670acd346d0f58553a7a725f6c8d4da17a73cb524cde606517d581bbc487dd
font_02_sfnt_off00010ffb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FFB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1