Malicious PDF — malware analysis report

Static analysis result for SHA-256 ddf28a5bb5a29dc9…

MALICIOUS

PDF

68.1 KB Created: 2021-09-27 03:24:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 19d1870be5078c2f840e55c0dae0f6db SHA-1: 8a15c75dd3baaeb5923e4445f0ecedba99217122 SHA-256: ddf28a5bb5a29dc9ff394393a6b39d2c55dbfa53a5a17e155b393b067197e350
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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=proxy+of+1377x PDF link annotation
    • https://psfund.org/public/uploads/files/cms_files/xizifu.pdfIn PDF document text
    • http://gibisch.biz/files/files/60180162827.pdfIn PDF document text
    • http://airmon.hu/images/files/87311442678.pdfIn PDF document text
    • http://khiconghoixuancong.com/Khicong/admin/userfiles/file/11799512596.pdfIn PDF document text
    • http://ledseoul.com/userData/board/file/41395996538.pdfIn PDF document text
    • https://www.rosebankprimary.co.za/inc/ckfinder/userfiles/files/dijofoluxananofavovadize.pdfIn PDF document text
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1614d052549240---45198968710.pdfIn PDF document text
    • https://calson.garment-pro.com/ckfinder/userfiles/files/17630260355.pdfIn PDF document text
    • https://shreegroupco.com/userfiles/file/93615561638.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/77cd7d6a591a7a978da7a6e538fe523e/zarujibel.pdfIn PDF document text
    • http://garmaclima.com/uploads/ckfinder/files/sozorukalekew.pdfIn PDF document text
    • http://educaholistica.com/resources/img/imagesck/files/77846644736.pdfIn PDF document text
    • http://solamsys.com/userData/board/file/veviwexewomexamumudu.pdfIn PDF document text
    • http://theonejsc.com/userfiles/file/jexakojikenor.pdfIn PDF document text
    • https://hotel-la-licorne.fr/userfiles/file/63864716229.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/161356cc095940---wudedewobike.pdfIn PDF document text
    • https://nslogisticservice.com/userfiles/files/93259599261.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161412f544f0b8---98313840115.pdfIn PDF document text
    • http://anabakorea.jp/userfiles/file/garirizidokufet.pdfIn PDF document text
    • http://pm-ural.com/uploads/files/68514428851.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210906_084411.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/t77vf5pq5pgah96528i92g059g/wonigofo.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_off0000acef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACEF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c501.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC501 15860 bytes
SHA-256: 15991bd53f7deeb64369fb8cb48f8ff40ff8ae4e2c19a13a826ed3bce2f93171
font_02_sfnt_off0000ed5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED5E 9896 bytes
SHA-256: 19b1d21e7c34fc4e8f1907595b1cde22565ffd5dda944dc26cfa6a24f1c014f8