Malicious PDF — malware analysis report

Static analysis result for SHA-256 87ea00bef665c5fb…

MALICIOUS

PDF

87.3 KB Created: 2021-09-07 23:08:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 28bdb0a4d7813cb074c299d6cc771d2e SHA-1: cca30a4543b869c964ecc1c71b747cbaab2751d7 SHA-256: 87ea00bef665c5fb8da12854e3f0a4be088c86329cb07449d735285a600ca9a0
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting. Heuristics indicate this is a link farm, a common tactic for phishing or distributing further malware. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://stdtekstil.com/upload/ckfinder/files/senujativowurolovojekufoj.pdf In PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1608797b6a443c---jejijotoziloridazij.pdfIn PDF document text
    • https://p99.tw/pro_pic/files/26967595223.pdfIn PDF document text
    • http://zhuxintrading.com/uploads/ckfinder/files/20210824/16297810254248.pdfIn PDF document text
    • http://broadmoor77.com/clients/39738/File/58927727863.pdfIn PDF document text
    • http://bijverhoeven.nl/uploads/files/savipelevimilibu.pdfIn PDF document text
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160b898be2003d---24732009043.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1609dade913d49---69811468566.pdfIn PDF document text
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609840f23d60c---56148441353.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1607c9d45195be---52869185847.pdfIn PDF document text
    • http://studiosaletta.it/userfiles/files/49910815644.pdfIn PDF document text
    • http://ippon.lv/uploads/File/basasunuvoketon.pdfIn PDF document text
    • http://www.thebetterinsurance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dd74c3cef70---mufajupu.pdfIn PDF document text
    • https://sakkestadbil.no/userfiles/file/44954212974.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/zozuxivapusuworupirosikon.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/9297130649.pdfIn PDF document text
    • https://kingwrapcarspa.com/upload/files/kokojijobudategate.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/3598859522.pdfIn PDF document text
    • https://rachelrom.com/rescontent/file/82914872019.pdfIn PDF document text
    • http://fittbike.hu/files/file/badibimeko.pdfIn PDF document text
    • http://gruppocinofilomarsalese.com/userfiles/files/87896507812.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=listening+actual+test+vol+6+pdfPDF link annotation
    • http://crossfit28.com.s125853.gridserver.com/siteuploads/editorimg/file/41694473619.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_off0000e51a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE51A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2C 21544 bytes
SHA-256: a3b4b458ab5917bad646a4e41c024be25c550c9f4cfc296bfb8e66b81b389438
font_02_sfnt_off00013632.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13632 10984 bytes
SHA-256: 86a451580c73c37b5d0566f9ce5d5ecd6cbd06c0d2c9b5f1d111ac2ab9ad4ef5