Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7948f9434051d18…

MALICIOUS

PDF

93.3 KB Created: 2021-10-07 08:58:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a8f36121b35d04c82a3415e41c161f70 SHA-1: 3872615d3df41a836593e7844e7a02486e2d46b4 SHA-256: b7948f9434051d18ff31942836416ff8b05c39c05badcbde20e382fb76ad17f9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It functions as a link farm, containing numerous URLs that point to external websites, many of which appear to be compromised or disposable hosting. The primary purpose seems to be directing users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://irlanc.ru/uplcv?utm_term=betrayed+meaning+in+telugu PDF link annotation
    • https://quanghuydulich.vn/img_duhoc/files/3099846528.pdfIn PDF document text
    • http://studiobaliva.eu/userfiles/files/zenosupimit.pdfIn PDF document text
    • https://best-turbos.com/wp-content/plugins/super-forms/uploads/php/files/05914ec1bbca55751810d155905196a8/72595446669.pdfIn PDF document text
    • https://balarampurblock.in/ckfinder/userfiles/files/87307773335.pdfIn PDF document text
    • http://cn-biyoute.com/d/files/38519037018.pdfIn PDF document text
    • https://www.nvsrolko.org/ckfinder/userfiles/files/70541637634.pdfIn PDF document text
    • https://ngonluathan.vn/images/ckeditor/files/22031741724.pdfIn PDF document text
    • https://zenmobile.in/jaipriyart/uploads/files/83541261244.pdfIn PDF document text
    • https://jasmijnbloemengroen.nl/userfiles/file/479347306.pdfIn PDF document text
    • https://euinsuti.uniluxgym.ro/app/webroot/files/userfiles/files/zosezejutawixopu.pdfIn PDF document text
    • http://profiklub.sanswiss.cz/files/file/8502450636.pdfIn PDF document text
    • http://xn--42-6kcdlkbomh7beggito5p.xn--p1ai/userfiles/file/befuze.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615db63c10e65---ziledupulef.pdfIn PDF document text
    • http://www.morrisjones.co.uk/EditorImages/file/tamogisebokavadixid.pdfIn PDF document text
    • https://cambodiadriverservice.com/userfiles/file/34524213490.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/161599aac6a804---62972993206.pdfIn PDF document text
    • https://walterchiropracticclinic.com/home/walter/public_html/ckfinder/userfiles/files/kewolexusoropibarab.pdfIn PDF document text
    • http://beckydavidsonhomes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d351dd7576---15844092631.pdfIn PDF document text
    • http://enricobarraco.com/files/65393271032.pdfIn PDF document text
    • http://ghefootmassage.com/fckeditor_userfiles/file/24988030256.pdfIn PDF document text
    • http://szzxwx.com/Upload/Upload/file/202192091314869.pdfIn PDF document text
    • https://marljivo.hr/UserFiles/files/76238199650.pdfIn PDF document text
    • http://portaldo.eu/contenuti/upload/file/23588012168.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_off0000faa7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA7 10568 bytes
SHA-256: e06ab6a468ff48fd67fc40381d1d223eefa34f58207ffb5ac36160e37e1606d8
font_01_sfnt_off00011288.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11288 23032 bytes
SHA-256: 774806803519a87ef0ee43fd54d658305da866cfba955d1cf5ef0a9bfb42ef26
font_02_sfnt_off00014d68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D68 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1