Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a6d7c2342d7d010…

MALICIOUS

PDF

79.4 KB Created: 2021-09-15 11:22:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 96e5939f82122a8da3b86bf0e83570b0 SHA-1: 5a6fef8e9b25ae49735214faad58ef9b68fbf501 SHA-256: 8a6d7c2342d7d010c92936121bc0e83b6976e128a7ae79bbc1242753d5a983c0
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to disposable domains and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://nayyaralidada.net/alpha/ckfinder/userfiles/files/80559844144.pdf In PDF document text
    • https://ppkh.net/userfiles/file/89026160160.pdfIn PDF document text
    • http://shijijiaming.cn/filespath/files/20210904200911.pdfIn PDF document text
    • https://ckeditor.pamlskovnik.cz/ckfinder/userfiles/files/tizajekalizazoduxapu.pdfIn PDF document text
    • http://satthachkhe.vn/image/file/66083446481.pdfIn PDF document text
    • http://infinijewelry.com/userfiles/file/nevimiwemewakepi.pdfIn PDF document text
    • http://elektromig.pl/userfiles/file/fuduxepata.pdfIn PDF document text
    • http://www.tiendadelbordado.com/ckfinder/userfiles/files/giruzokufifewonul.pdfIn PDF document text
    • http://langmoon.jp/js/upload/files/nilojokutetagarov.pdfIn PDF document text
    • http://maxbrio.kr/files/files/48648129531.pdfIn PDF document text
    • https://abhrian.com/userfiles/files/82721412417.pdfIn PDF document text
    • https://gospel-streams.com/asset/ckfinder/userfiles/files/xitodu.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/3e0cuf2lttr886dpcndl83vco2/87655445125.pdfIn PDF document text
    • http://momsystem.ru/public/file/puzepenizer.pdfIn PDF document text
    • https://rubfila.in/files/file/wolekakadib.pdfIn PDF document text
    • http://www.trimbleexpress.sk/wp-content/plugins/formcraft/file-upload/server/content/files/1614111bb9c995---57413080462.pdfIn PDF document text
    • https://eghamatkade.com/basefile/eghamatkadecom/files/28524199832.pdfIn PDF document text
    • http://hferrynetworks.com/FileData/ckfinder/files/20210914_C6FC9B89A7F20892.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/veviponazusuj.pdfIn PDF document text
    • https://htcpost.vn/vietpost.vn/img_content/file/46296176466.pdfIn PDF document text
    • http://chieusangducphat.com/uploads/userfiles/file/2290345478.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/soseronujolabumudavol.pdfIn PDF document text
    • http://fqcycpa.com/jingkelun/userfiles/files/20210913020745.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=pixel+4a+icons+at+top+of+screenPDF 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_off0000d1a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1A7 17432 bytes
SHA-256: 4cd17851a65753f976799bab3338b45b23a3419ba6621bd97f29f578125cfaa4
font_01_sfnt_off0000ff11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11728 10652 bytes
SHA-256: 57a3a6a3452d29e21697e748e29a57c1dbb7e54f3d656709c0f72b61b4fb88d9