Malicious PDF — malware analysis report

Static analysis result for SHA-256 4625724c6dcb2319…

MALICIOUS

PDF

78.5 KB Created: 2021-09-11 03:48:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: 7befbb8da9db6a5e3644400b57be05b1 SHA-1: 45d462cc24c9f34c3e71c66f707a233a97d2a71d SHA-256: 4625724c6dcb2319c3a034fed476566cc0eb2eda056653321e8612e19ab58d6d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic suggests the document is designed as a link farm, pointing to numerous distinct hosts, which is a common tactic for phishing or distributing further malware. The embedded URLs, while some are marked benign, contribute to the overall suspicious nature of the document's structure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/13dd33b4e1643b40e0917d35852a9194/kuxujeginipaz.pdf In PDF document text
    • https://aymexco.ro/ckfinder/userfiles/files/94907819660.pdfIn PDF document text
    • http://citescolairedeledit.com/include/file/wemijeziburuweleruvaju.pdfIn PDF document text
    • http://gidromall.ru/img/uploads/file/70620949022.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/86874899973.pdfIn PDF document text
    • http://onlinemidias.com/ckfinder/userfiles/files/95664155834.pdfIn PDF document text
    • https://my-natural-style.net/upload/files/31856369670.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/14019022111.pdfIn PDF document text
    • http://lotusromeo.fr/app/webroot/files/userfiles/files/daxedonobabanusama.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/lataxirew.pdfIn PDF document text
    • http://circolosilverblufitnessclub.eu/userfiles/files/werikunanasopumezedotex.pdfIn PDF document text
    • https://northwestconvention.cz/data/files/99891887203.pdfIn PDF document text
    • http://onlinecommerce.bg/uploads/pages/files/90658766732.pdfIn PDF document text
    • http://annassteen.com/ckfinder/userfiles/files/puvemesetikades.pdfIn PDF document text
    • https://gornjastubica.hr/files/vanor.pdfIn PDF document text
    • http://trungtinjsc.vn/upload/FCK/file/99182310359.pdfIn PDF document text
    • http://www.bluefashion.cz/ckfinder/userfiles/files/kefurazilevobev.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134ec3877cff---kitizowo.pdfIn PDF document text
    • http://autoachtercamper.nl/userfiles/file/torefawavetinejokefirurul.pdfIn PDF document text
    • http://imhyuk.com/imhyukeditor/userfile/file/44001456503.pdfIn PDF document text
    • http://thebankcardservice.com/uploads/files/12697856290.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210911083224.pdfIn PDF document text
    • http://henanshuangxin.com/d/files/tapefin.pdfIn PDF document text
    • http://unibeauty.com.br/ckfinder/userfiles/files/zubezojokijiwome.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=hero+academia+tv+showPDF 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_off0000d0d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0D0 10628 bytes
SHA-256: 6d4bbb611651c41523644f11ab044c322b52b6382423bb55695af81c4699397b
font_01_sfnt_off0000e932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE932 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010144.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10144 16864 bytes
SHA-256: 6702b6ba3179bb51f509299f58c4fae73a3f2c83cfbffa8104e36c3e2589c9f9