Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cb98779f45d6bcf…

MALICIOUS

PDF

70.9 KB Created: 2021-09-25 04:42:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1c72e7a64160f8b40e1ed6a47c7665a4 SHA-1: 56f053f9860ffcdf6c98a75cf2f3b8045e592066 SHA-256: 8cb98779f45d6bcfe69130418dabc3d75b04435210fc89459f1a5983fb2fa7a8
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a large number of links pointing to potentially disposable domains, suggesting an attempt to obscure the true malicious destination or to distribute various payloads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely involving phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://maconlux.lu/userfiles/files/wibisesesalobazomofos.pdf In PDF document text
    • https://economiadecomunion.com/ckfinder/userfiles/files/94633595893.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/5edc68062f49878ac99a978a3eb5279d/42648270678.pdfIn PDF document text
    • http://a1climbing.com/userfiles/files/lotavuwomipotamebabebiki.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16134234bd0711---98557459841.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/24053999964.pdfIn PDF document text
    • http://stroisvias.ru/userfiles/file/favukejasonijomavebuxa.pdfIn PDF document text
    • http://chrisdepanneservices.com/Sites/cds/files/kujabosatotipewabo.pdfIn PDF document text
    • http://tufaghanafc.com/js/ckfinder/userfiles/files/51491711109.pdfIn PDF document text
    • http://lynxauto.ru/userfiles/file/42888477107.pdfIn PDF document text
    • http://studiotecnicofrisoli.com/userfiles/files/fodoze.pdfIn PDF document text
    • http://avvocato-callegaro.it/public/file/96135210114.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/161498357b3b77---60074943767.pdfIn PDF document text
    • https://gedayapi.com/userfiles/file/56035435034.pdfIn PDF document text
    • http://khachsandomino.com/hinhanh_fckeditor/file/27580427125.pdfIn PDF document text
    • https://alebusph.centralcms.cloud/galeria/files/95820984091.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/81807247504.pdfIn PDF document text
    • http://cloverdiamond.com/file/55498756838.pdfIn PDF document text
    • https://mumegram.com/userfiles/file/tifozekomapeximi.pdfIn PDF document text
    • http://kuhomania.ru/ckfinder/userfiles/files/perexotatopofurafo.pdfIn PDF document text
    • http://coaching-scolaire.net/userfiles/file/96014025072.pdfIn PDF document text
    • http://altiro.nl/home/tjerk/file/93918492570.pdfIn PDF document text
    • http://www.pics4us.de/userfiles/file/94129801565.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=bloons+td+6+apk+mod+unlimited+moneyPDF 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_off0000b03d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB03D 10980 bytes
SHA-256: 71e363d2593893e044e7c2a35d47f6872881bb3bc65fb52d11f926a4c9f7c8d2
font_01_sfnt_off0000c9cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9CD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e1df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1DF 17400 bytes
SHA-256: 8e5c220e180a5cc654a21172170a3cbdcb55fe4f2a40caf1591b3effd43bf304