Malicious PDF — malware analysis report

Static analysis result for SHA-256 a83bdbd4740affb8…

MALICIOUS

PDF

71.4 KB Created: 2021-09-29 14:16:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 187bf9aa59c2b12cffc63429a6e681ab SHA-1: a50cec59c3bcc4aa0529a4efcc2e7b94c7f6be6d SHA-256: a83bdbd4740affb8e0cd804bedef7ea3a255cef67e62669eddb642019b89ead6
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external URIs, indicating it's designed to redirect users to malicious content. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic and numerous unknown reputation URLs suggest a link farm intended to obscure the ultimate destination. ClamAV and ML classifiers confirm its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/ik65vjdtmjsci64foiaju658sk/37169335193.pdf In PDF document text
    • http://wdnederland.nl/file/gododovagetibi.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/94753077480.pdfIn PDF document text
    • https://www.hsbofmn.com/ckfinder/userfiles/files/zisapunibefenomonowo.pdfIn PDF document text
    • http://tsrmmessina.it/userfiles/files/81413996081.pdfIn PDF document text
    • http://olivetheater.com/userData/board/file/biderupaselubuvanejo.pdfIn PDF document text
    • http://jungam21.com/upfiles/file/1631809337.pdfIn PDF document text
    • https://www.esicm-old.org/admin/lib/ckfinder/userfiles/files/xokobiluzebasatobaso.pdfIn PDF document text
    • https://creativitagh.com/pevron/www/img/file/45102915790.pdfIn PDF document text
    • https://foundryindia.org/userfiles/file/nanusesukotigatebinigub.pdfIn PDF document text
    • http://uro-medical.pl/zdjecia/fotki/file/fafugisunavigogawenivomog.pdfIn PDF document text
    • https://24emk.ru/ckfinder/userfiles/files/60536092164.pdfIn PDF document text
    • http://sm300159.agchost.com/userfiles/files/76330240434.pdfIn PDF document text
    • http://lingeriedediva.com/UploadFile/file/2021091518083873499.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-17/20210917110244487231.pdfIn PDF document text
    • https://kottayammedicalcollege.org/CMS/ckfinder/userfiles/files/36981994634.pdfIn PDF document text
    • https://b2b-intelligence.it/uploads/file/buxonetakiwogatu.pdfIn PDF document text
    • https://sdhouse.info/ckfinder/userfiles/files/57263231185.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/b6b915a3c97dcf01f7ecada96d855057/13519932226.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109201003027323.pdfIn PDF document text
    • http://maduraicaterers.com/app/webroot/js/ckfinder/userfiles/files/kijabivegoba.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/zimufanoli.pdfIn PDF document text
    • https://micro-logic.ro/images/uploaded/file/xikonitetewiroroboboza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=anime+apk+for+android+tvPDF 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_off0000b0af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0AF 18220 bytes
SHA-256: a79cc43c5110c895ff0d6a0cb4d68ba93d8bee27e142c7d792a96c8680f2e260
font_01_sfnt_off0000e01e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE01E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f835.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF835 10584 bytes
SHA-256: 2ca41d69711aed61d1057a43911876c150174ef05cdc5b7d290bf6bea62466e9