Malicious PDF — malware analysis report

Static analysis result for SHA-256 af47cd0a3ea023a1…

MALICIOUS

PDF

76.3 KB Created: 2021-09-09 07:50:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ba5be6d53460f633d88cff916c6cb827 SHA-1: f5ef9ee31ed26ef7e5334f7806f51b327a60ac41 SHA-256: af47cd0a3ea023a1f61ce0b9837956488eaf3270d7139fac9813fd35536cc564
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for malicious PDFs. The PDF also contains numerous external URIs pointing to various domains, many of which are likely part of a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://laborke.ru/uplcv?utm_term=probability+and+statistics+for+engineers+and+scientists+9th+edition+solution+manual PDF link annotation
    • https://illustrations.noche.fr/images/files/latobepipasufofop.pdfIn PDF document text
    • https://stgeorgedentalcare.in/ckfinder/userfiles/files/12055369387.pdfIn PDF document text
    • https://cardolf.ro/files/29489456509.pdfIn PDF document text
    • https://callmarkinvestments.com/callmark/files/28019011030.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161344116054f5---tepevinubiluwevawedegofog.pdfIn PDF document text
    • http://teleserviciomalaga.com/ckfinder/userfiles/files/bagaxuxowuxegel.pdfIn PDF document text
    • http://microcement.ua/userfiles/file/21068114580.pdfIn PDF document text
    • http://antonio-pelella.eu/userfiles/files/45329728307.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/gobekirovexa.pdfIn PDF document text
    • http://asorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tebofuxutakolenimenaxolab.pdfIn PDF document text
    • http://classicalgardenstatues.com/uplds/file/86034625522.pdfIn PDF document text
    • http://toyteepee.com/uploadfiles/file/210902020046331958il5zz7.pdfIn PDF document text
    • http://erfaspot.com/resimler/files/42826606907.pdfIn PDF document text
    • http://larrysiegellaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/47304231130.pdfIn PDF document text
    • https://tapetcenter.ro/app/webroot/files/userfiles/files/gazerodowuzulig.pdfIn PDF document text
    • https://christianbelieversmatrimony.com/web/christiansbelieversmatrimony/photos/ckeditor/files/jonazeweturosezuravirugik.pdfIn PDF document text
    • https://linlinline.biz/js/ckfinder/userfiles/files/47084995067.pdfIn PDF document text
    • http://evrofurnitura.by/elax-furnitura.ru/uploads/files/dovedabinokasulefoz.pdfIn PDF document text
    • http://ciba.lv/uploaded/file/31227022110.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/1612f6208ebaa7---10655019180.pdfIn PDF document text
    • http://finalstage.biz/js/upload/files/gudegowape.pdfIn PDF document text
    • http://fujavietnam.com/images/Download/mevawanajusenote.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_off0000c30c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC30C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000db23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB23 11448 bytes
SHA-256: 7cd09a8a4fa79e8218566c7604be424ee869bb6b61b5a74bb29cb5449fad1c8c
font_02_sfnt_off0000f5d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5D1 17632 bytes
SHA-256: 80ccf8277b15436439166cc4d1c19f695434f16adcec5f083509b3636d2187e8