Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f49cbd8d8b1c18f…

MALICIOUS

PDF

79.6 KB Created: 2021-09-18 13:43:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1e5f964528108a7cacba8a4ce04d7170 SHA-1: 9219aca5d4b1e9bb16043b921676c960b67731c2 SHA-256: 7f49cbd8d8b1c18fe4273362a4eafcf69172c69fdc9b9c5b65d377bcdee7f01b
126 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to various domains, many of which appear to be part of a link farm. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic further supports this, indicating a pattern of using disposable hosting for link aggregation. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to facilitate the redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 5

  • 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.
  • 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://arndt-fahrschule.de/userfiles/file/dufejamovebaru.pdf In PDF document text
    • http://vnationwide.com/userfiles/files/60682374483.pdfIn PDF document text
    • http://khachsandomino.com/hinhanh_fckeditor/file/rusoxenax.pdfIn PDF document text
    • http://elitakhealing.com/ckfinder/userfiles/files/mibenopadobi.pdfIn PDF document text
    • http://deaprogettazioni.it/userfiles/files/91720086968.pdfIn PDF document text
    • http://nanobubblevietnam.com/uploads/userfiles/file/xolilaropef.pdfIn PDF document text
    • https://phnews.ro/files/file/12516345614.pdfIn PDF document text
    • http://biondiairsystem.it/userfiles/files/kebiridusos.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/62385418178.pdfIn PDF document text
    • http://pjzhengwang.com/upload/file/20210916_061311_145.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/78885928268.pdfIn PDF document text
    • https://granitnet.hu/editor_up/4382245306.pdfIn PDF document text
    • http://playitdirect.ca/ckfinder/uploadfiles/files/faponafena.pdfIn PDF document text
    • https://maintogelonline.bet/contents/files/7949804997.pdfIn PDF document text
    • https://noelex22.org/userfiles/file/68744086424.pdfIn PDF document text
    • https://sierrainstruments.cn/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/27366996570.pdfIn PDF document text
    • http://hasomedia.com/userfiles/file/fojizikizuroduxemiwusozim.pdfIn PDF document text
    • http://rajskiewakacje.pl/userfiles/file/vasofududererigabokaj.pdfIn PDF document text
    • https://www.food-equipment-store.com/fckeditor/uploads/file/3416656176.pdfIn PDF document text
    • https://best-label.com/upload/files/kivipikewonizonowuminelop.pdfIn PDF document text
    • http://phuclocvienjsc.com/uploads/image/files/43922475860.pdfIn PDF document text
    • http://pampa.be/uploads/userfiles/files/21179578031.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/75122665632.pdfIn PDF document text
    • http://www.sushmitamukherjee.com/fckimages/file/65307378633.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=best+auto+change+wallpaper+appPDF 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_off0000d530.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD530 10800 bytes
SHA-256: d3ed4b7ed7409b352766eb56be9312fbeb274d4a5a7b9c0e971ae897a8bbb780
font_01_sfnt_off0000ee2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE2A 16620 bytes
SHA-256: 311a0a5303f40af6c515d06904d633f2c963868c43241f6addc63fe8f2ec4ad6
font_02_sfnt_off000118ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1