Malicious PDF — malware analysis report

Static analysis result for SHA-256 684c43fe5ec35bab…

MALICIOUS

PDF

74.1 KB Created: 2021-09-12 02:14:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 5bb0f4bad31872f5c09343d8ee358c83 SHA-1: 9af436b7c2c64df09c15dd7e2dc3e012fee5935d SHA-256: 684c43fe5ec35babba0e42ed06c34f3b73e71eaa92ff61fcf917c70ebcbbb09d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, exhibiting characteristics of a phishing or malware distribution lure. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the document is designed as a link farm on disposable hosting, with numerous distinct hosts pointing to PDF files. While no scripts were extracted, the presence of many unknown URLs suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://cariboohose.com/userfiles/file/29111946745.pdf In PDF document text
    • http://capesociety.ca/uploads/files/12673892841.pdfIn PDF document text
    • https://ural-aiti.ru/admin/ckfinder/userfiles/files/gotewuwakexaxujotezixo.pdfIn PDF document text
    • http://saharun.org/uploads/ckfinder/userfiles/files/jorovagavedozujozuge.pdfIn PDF document text
    • https://hearing-outlet.com/uploads/files/202109100151508443.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613708ee5c8a2---88875622069.pdfIn PDF document text
    • http://j1ent.com/userfiles/file/20210910090454.pdfIn PDF document text
    • https://mtmhomeschool4art.com/mycms/uploadedimages/editorUploadedImages/file/950463442.pdfIn PDF document text
    • https://stephankeppel.com/userfiles/file/zesukozexigafis.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/23310712135.pdfIn PDF document text
    • http://nexxosrealty.com/userfiles/files/sibowokitir.pdfIn PDF document text
    • http://pb-book.com/user_file/file/wipumegipefukizukowubom.pdfIn PDF document text
    • http://radiopoint.cz/userfiles/file/84091657964.pdfIn PDF document text
    • https://www.autopsrus.com/ckfinder/userfiles/files/30144518136.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/89269042470.pdfIn PDF document text
    • https://giriconsultancy.com/content_files/files/masodenexomegoxav.pdfIn PDF document text
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161393fb45c5de---ferusibekixatasot.pdfIn PDF document text
    • https://igruppe.no/ckfinder/userfiles/files/6734752253.pdfIn PDF document text
    • https://mygenius.ru/admin/ckfinder/userfiles/files/24215140581.pdfIn PDF document text
    • http://e-kva.ru/admin/ckfinder/userfiles/files/zutanigopepiwizanuvun.pdfIn PDF document text
    • http://bouwbedrijfansing.nl/userfiles/file/85957341602.pdfIn PDF document text
    • https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/34704565543.pdfIn PDF document text
    • http://lauraestetica.com/userfiles/files/ripavedifamesekapu.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/nawedobaxemupifebo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=aplikasi+edit+foto+android+kekinianPDF link annotation
    • 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_off0000bf9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF9F 10564 bytes
SHA-256: 73f50c71d7fa72a7a1abb8d69e0d0d13a7924b4b76264f100b4e6dc85d4a290c
font_01_sfnt_off0000d7dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD7DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000efef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFEF 16456 bytes
SHA-256: 1b28ce85566413592389ce79ee8ea7d041513051a2bcee50332e05296ff7777a