Malicious PDF — malware analysis report

Static analysis result for SHA-256 d7921b481a150326…

MALICIOUS

PDF

89.5 KB Created: 2021-09-22 22:53:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2b7b4f5f90f4e0280272d0e507995cf6 SHA-1: 499c8cd3e30c1004648d4e6bb3d963d8c073c9d6 SHA-256: d7921b481a1503267564a027b43338ed5184f3453579a099be52cb1db422a8b0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. The file contains numerous external URIs and is structured as a link farm, suggesting it is used to redirect users to potentially harmful websites. The presence of external URIs and the link farm structure points towards an attack pattern involving directing users to phishing or malware download sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

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 https://nuteuit.ro/ckfinder/userfiles/files/konuxo.pdf In PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/55912fd916192c6c523dbd223a93b6c4/37711925081.pdfIn PDF document text
    • http://thriftstorewebsites.com/flash/thriftstorewebsites.com/file/69957022443.pdfIn PDF document text
    • https://trsoftyazilim.com/genelresimler/file/wofifupemite.pdfIn PDF document text
    • https://geloracinta.com/contents/files/62082457038.pdfIn PDF document text
    • http://cnzgks.com/userfiles/file///10190605679.pdfIn PDF document text
    • http://mp-hd.de/data/aktualnosci_imgs/file/tadinegi.pdfIn PDF document text
    • http://lixupeng.com/uploads/files/20330133671.pdfIn PDF document text
    • http://nordicwalkingturak.hu/_user/file/namirosagoger.pdfIn PDF document text
    • http://worldnaturalfood.com/image/upload/File/kojereje.pdfIn PDF document text
    • https://aviatroglo.fr/IMG/file/rizukenufawanaf.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/gugadagotokijiwakufog.pdfIn PDF document text
    • http://methese.com/upload/files/94630662965.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/36825388933.pdfIn PDF document text
    • https://anup.bo/images/files/48167168499.pdfIn PDF document text
    • https://semineebrasov.ro/printuri-fi/files/92010825219.pdfIn PDF document text
    • https://bimetoor.com/basefile/bimetoorir/files/buromu.pdfIn PDF document text
    • https://thehouseconcert.com/ckfinder/userfiles/files/wokasirar.pdfIn PDF document text
    • http://texinpack.com/uploadfile/file///2021091714525145.pdfIn PDF document text
    • http://artecgroupservices.com/imagenes/file/kajidibodofusivejes.pdfIn PDF document text
    • http://oio.cn/uploadfiles/files/rekeguvaxubuvo.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/79840145444.pdfIn PDF document text
    • http://qbcar.ru/ckfinder/userfiles/files/51081704644.pdfIn PDF document text
    • http://xn--jt2b56wn0ap2a.com/upload/file/202109060108559426.pdfIn PDF document text
    • http://fewo-spreewald-schoetzigk.de/brandenburgtag/img/editor/file/29601521255.pdfIn PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/gijadegokevewuru.pdfIn PDF document text
    • https://coop-alternatives.fr/images/images/13264392402.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=install+flutter+di+visual+studio+codePDF 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_off0000f6b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6B5 18752 bytes
SHA-256: 7b308799df3a0e9304eafc8a6b7cce93278f17efd2cf36dbd2ca5d4922d5407d
font_01_sfnt_off00012737.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12737 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013f4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F4E 10584 bytes
SHA-256: 8a1da40af3b7d678e66f328f4d8678c70a46ecfad2a93fd5eca916be3582c2c0