Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1b87045f799dacc…

MALICIOUS

PDF

76.2 KB Created: 2021-09-11 03:56:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 226dff40d5d40238b558f4d1377911b1 SHA-1: 7cc295b549ec14154069884ec483c76acde9661c SHA-256: a1b87045f799daccc7623c930b36ec3e81ef601fa9da53ed5b0b180859e6ed53
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, with one pointing to a disposable domain, indicating a link farm designed to obscure the ultimate destination. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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 http://zhouzhuanx.com/v15/Upload/file/2021911548299665.pdf In PDF document text
    • https://tagoproperties.com/ckfinder/userfiles/files/mekuwowaxenurojibamalafi.pdfIn PDF document text
    • http://agilesolutions.in/uploads/4475573310.pdfIn PDF document text
    • http://vln.nl/files/file/77885661423.pdfIn PDF document text
    • http://chinatriage.com/ckfinder/userfiles/files/58175760764.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/qlej8c227e2ehakha1uh45l9ua/77249447246.pdfIn PDF document text
    • http://acmemask.com/upfiles/editor/files/87750217382.pdfIn PDF document text
    • http://sergeybazarov.ru/file/telawakunivop.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16135dedfb8323---zebowuvivezeperemeg.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/mugupikixiwemolek.pdfIn PDF document text
    • https://mchs.kz/userfiles/File/zusef.pdfIn PDF document text
    • http://squash-fitness.cz/userfiles/file/sepikuvili.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/xenob.pdfIn PDF document text
    • https://emenu.hu/editor_up/mezawev.pdfIn PDF document text
    • http://wildzipper.com/clients/wildzipper/userfiles/file/6487962449.pdfIn PDF document text
    • http://luluscafeonline.com/uploads/files/6701091080.pdfIn PDF document text
    • https://raiporjai.com/piceditor/file/14326531890.pdfIn PDF document text
    • http://fatename.com/uploads/files/202109081511389065.pdfIn PDF document text
    • https://pergamine.com/ckfinder/userfiles/files/28447523665.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/gaguxel.pdfIn PDF document text
    • https://rizecanreklam.com/images/file/xubesiduforofuzigori.pdfIn PDF document text
    • http://emanuelmlevin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tuzitud.pdfIn PDF document text
    • http://cautrucpalang.vn/webroot/img/files/80969767688.pdfIn PDF document text
    • https://ivanda-commerce.hr/userfiles/file/45002512513.pdfIn PDF document text
    • http://yanartextil.com/firma/files/54028856733.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=paladin+of+vengeancePDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off0000cc5c.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0xCC5C 17436 bytes
SHA-256: 118801a8e2784c1b3bbb5fa31b0078565743a6658acc23e2e0e7fb15bd7b6f94
font_00_sfnt_off0000b44b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB44B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e699.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE699 14732 bytes
SHA-256: ff6a465e271a06a240447baa6c74f5fe19d251a47363822050c3c9b80db37812
font_03_sfnt_off00010baf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BAF 10352 bytes
SHA-256: ae82a47a27e31c2a1eda525d65e3c4f352787dbff0f05e1abe4e77b27ed833c5