Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c99b9441e050069…

MALICIOUS

PDF

83.4 KB Created: 2021-08-28 11:02:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: aab2e960af5bf969f7e1050cf17c52b3 SHA-1: daa2c2b93683b371a4d8f1c159172904b78fb913 SHA-256: 4c99b9441e05006910889fe6c407fa977285e4ac2bbb38f2ab4e11cb153cdf36
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The file contains numerous links to compromised websites, suggesting it is part of a phishing or malware distribution campaign. The presence of external URIs and link farms on disposable hosting further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://coretry.ru/uplcv?utm_term=chlorine+in+the+periodic+table
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/92518562581.pdf
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/cklrh71qjomsr1qqbvnl22qr72/13935205661.pdf
    • http://ever-pioneer.com/upload/files/95987192349.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf1bc75fa6---2202921199.pdf
    • http://chapelguild.com/images/usr/xomemodoxovabetiwusefabof.pdf
    • http://kamkmori.cz/ckfinder/userfiles/files/risekawurusivilebakudaru.pdf
    • http://novelinternationalschool.com/ckfinder/userfiles/files/parilojetej.pdf
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b9275a1d0d---8908077767.pdf
    • https://rajaketiga.com/contents//files/8062667015.pdf
    • http://jyotiacademicpress.org/uploads/file/29038306885.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/32e91c0bc83c7c0acb5d065f36d2b114/taduginojigifewuzetupad.pdf
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/16109365b67807---50860079700.pdf
    • https://feniks9.ru/ckfinder/userfiles/files/finip.pdf
    • http://master-br.ru/img/file/78021837835.pdf
    • https://muguet.fr/sites/default/files/file/74792212439.pdf
    • http://ypperfect.com/ckfinder/userfiles/files/53231323467.pdf
    • http://kythuatviet.vn/uploads/userfiles/file/40330739413.pdf
    • https://neavocats.com/wp-content/plugins/super-forms/uploads/php/files/39639e9908993e11a12136e50ac43871/xodugebogabijobuf.pdf
    • http://pro-group.ru/userfiles/files/15164202984.pdf
    • https://jesssmithtri.com/jesssmith/ckfinder/userfiles/files/liponaxataxadimisemozos.pdf
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608ae259ba707---darafudu.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160c85504d6621---vojexegewisebo.pdf
    • http://superplasticizer.cn/d/files/89722682042.pdf
    • http://yuha.be/_files/file/15218921078.pdf
    • http://ventilatoryzlin.cz/images/file/33594114074.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dc34.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC34 16792 bytes
font_01_sfnt_off0000f446.bin
6a5f20e6b3900f64a97c1295edf4fd14c65effa7708d54634cb25cc75b5f728e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF446 19468 bytes
font_02_sfnt_off00012769.bin
90e5e8f779c3087791be99dc4c642e3b7a14f87a59ea0dfaa442a6773ebf5533
pdf-font-stream PDF embedded font (sfnt) at offset 0x12769 10616 bytes