Malicious PDF — malware analysis report

Static analysis result for SHA-256 388944c17cf5f8ea…

MALICIOUS

PDF

79.2 KB Created: 2021-09-08 23:25:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-17
MD5: da7667ab3eb827b01a822c1acdd06af9 SHA-1: 5c2eb4bb8ad0b87a6daf5a5b34ba042c31e0eb3b SHA-256: 388944c17cf5f8eab12c3f49abf49a4e2a804f65947c620f71f2a01d228237f7
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are part of a link farm hosted on potentially compromised or disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of UTM parameters like 'utm_term=tap+tap+app+to+download+pubg' suggest a deceptive purpose, likely to lure users to malicious websites for phishing or malware downloads. The ML classifier strongly supports the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 5

  • 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://irlanc.ru/uplcv?utm_term=tap+tap+app+to+download+pubg PDF link annotation
    • http://ain.proximeo.com/ckfinder/userfiles/files/22874346307.pdfIn PDF document text
    • https://ancoraeducacion.com/images/94891595252.pdfIn PDF document text
    • http://hakkabrothers.com/userfiles/file///xonazilafenibab.pdfIn PDF document text
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/pemapimeragavim.pdfIn PDF document text
    • http://cluboutletmoto.net/campannas/file/65613990734.pdfIn PDF document text
    • https://activsport.ro/userfiles/file/xavigibubotokaxavad.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/26293447271.pdfIn PDF document text
    • http://agapetown.net/ckfinder/userfiles/files/72749989831.pdfIn PDF document text
    • http://hatowo.com/app/webroot/uploads/files/xofal.pdfIn PDF document text
    • http://xn--z92bzy85x.com/userData/board/file/24460513892.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/30093628895.pdfIn PDF document text
    • http://timecraftz.com/userfiles/file/57565858941.pdfIn PDF document text
    • http://fourfoods.com/images/files/venexopiv.pdfIn PDF document text
    • http://logtech.cz/foto/Image/file/tarulojiti.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/7ec60c87537bb45f3bcb5290d7cad36a/38475063420.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16135c95241faa---81262567999.pdfIn PDF document text
    • http://misr-consult.com/userfiles/file/13980658055.pdfIn PDF document text
    • http://nenorm.com/files/files/davokuvasadeta.pdfIn PDF document text
    • https://fetogram.com/images/upload/files/nutepipoxerolowuvasal.pdfIn PDF document text
    • https://brakos.it/file/peritatekikuvexefuxisogib.pdfIn PDF document text
    • http://ombs.ru/uploads/files/bananekulejivijamuku.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/c5f3e0f8ce1e6e69f96394114c73e7ba/84625160166.pdfIn PDF document text
    • http://aquaclub.hu/userfiles/file/kesuwodanogogoxaraz.pdfIn PDF document text
    • http://tercovci.cz/files/file/nisipupefakitoju.pdfIn PDF document text
    • 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_off0000d16b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD16B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e97d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE97D 18084 bytes
SHA-256: ab1aa1d91663b51d2d1edee34b00db7d9bd669c5b88a007293887efd3505f37d
font_02_sfnt_off000117bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117BB 10364 bytes
SHA-256: 525d148c2bf76865fbb6c0e279073537e1e0c93b8179116b8ce5db8a8850c907