Malicious PDF — malware analysis report

Static analysis result for SHA-256 e4250eb5f447569b…

MALICIOUS

PDF

84.6 KB Created: 2021-09-19 02:33:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 525647b937b328e1c0d3e9d3347d9c62 SHA-1: 0a96d11a1c31412c44fb2d60725134fdc6ccacbc SHA-256: e4250eb5f447569b26b536d7aa214ff2896067dfebe2519cfcceabdf0eead1e3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised WordPress sites. The presence of PDF_URI and EMBEDDED_URL heuristics further supports the attack pattern of luring users to external content. No scripts were extracted, but the overall structure suggests a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://medvor.ru/uplcv?utm_term=android+some+apps+not+connecting+to+internet PDF link annotation
    • http://geraldinekilkelly.ie/fedowi.pdfIn PDF document text
    • http://nextgenship.net/upload/file/20210907163101234642.pdfIn PDF document text
    • https://halkapsikoloji.com/userfiles/file/24481625169.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/6820491210.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d04d246f0---gupedelikazewexowi.pdfIn PDF document text
    • https://eclipsetheaters.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a85825f8a---8701436268.pdfIn PDF document text
    • http://kozhencherrymtc.org/userfiles/file/wukukop.pdfIn PDF document text
    • https://www.uflo.edu.ar/ckfinder/archivos/documentos/gasote.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/22922578040.pdfIn PDF document text
    • https://puntodeplacer.com/userfiles/file/rikekonufazudib.pdfIn PDF document text
    • http://maksimetall.ru/files/xutidumofafov.pdfIn PDF document text
    • http://safires.cz/ckfinder/userfiles/files/49049543192.pdfIn PDF document text
    • https://altaamir.ipixpms.com/Rapport/public/assets/ckfinder/userfiles/files/neridafofafowazipidusisus.pdfIn PDF document text
    • http://aitrans.cn/UploadFile/file/F1202109092047539927.pdfIn PDF document text
    • http://mrcookie.tw/upload/editor/file/040247255366.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134ea4fcf0f2---tesubuxedipizedaxif.pdfIn PDF document text
    • https://aradovan.com/userfiles/file/64011278823.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/dddf7bc5a762109e34d6fb612cd34acf/rixuvube.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613634b3d5603---28483900706.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/5336921130.pdfIn PDF document text
    • http://kargo-box.com/uploads/files/34542832706.pdfIn PDF document text
    • https://tomclarkvoiceovers.com/userfiles/files/25692655434.pdfIn PDF document text
    • http://stjconsulting.it/userfiles/files/bugawaw.pdfIn PDF document text
    • http://oecschool.com/userfiles/file/65719646496.pdfIn PDF document text
    • http://twozonechickenlasvegas.com/uploads/files/86618808532.pdfIn PDF document text
    • http://fskyok.com/uploadfile/files/kaduxulibukukawome.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_off0000e697.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE697 17312 bytes
SHA-256: 059a7138cb1babfa12fa65ff2a3cc00eca942437cf6bc38c4ffe98da6eaffe24
font_01_sfnt_off00011389.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11389 10792 bytes
SHA-256: 1e16e147e1ac1333f1f0d06fd21097ae4ae9e7add1bb385cc051fc1ee8867929
font_02_sfnt_off00012c36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1