Malicious PDF — malware analysis report

Static analysis result for SHA-256 d840f8bf16172517…

MALICIOUS

PDF

77.1 KB Created: 2021-09-17 19:56:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 42334d7bc703ab8f887a4cdedc144e99 SHA-1: fb940c1fa3ef97aa233f1f10e68c96f8f4467fe8 SHA-256: d840f8bf1617251761686c4952efec8863bb83fd22a32cdaabdd08098e1ad992
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous embedded URLs pointing to disposable domains, characteristic of phishing or link farm operations. The PDF structure and embedded content suggest it's designed to redirect users to malicious websites, likely for credential theft or further malware delivery.

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 https://krisoc.ru/uplcv?utm_term=get+mobile+number+in+android+programmatically PDF link annotation
    • https://dacinsara.ro/fckfiles/file/72073760355.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/wazirasajofazakonujizovul.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/gijenavejadifi.pdfIn PDF document text
    • http://www.jysunshine-hotel.com/up_files/file/pexopogiseduzevusilumik.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/24df3732a76d74d34cc651e9f1626416/zameniwezutotokeboraxim.pdfIn PDF document text
    • http://romovi.net/sgi_userfiles/userfiles/files/jumotupolesabonuzup.pdfIn PDF document text
    • http://www.logistiekverbeteren.nl/ckfinder/userfiles/files/30681199206.pdfIn PDF document text
    • https://rh4-h1tapi-turbo.com/contents/files/zedujavakinu.pdfIn PDF document text
    • http://unseretochter.ch/images/file/10535234428.pdfIn PDF document text
    • https://dubaimotorcycletours.com/uploaded_images/files/nepezeduvosewama.pdfIn PDF document text
    • https://trisyscom.com/userfiles/file/35339307736.pdfIn PDF document text
    • http://silverspringabw.com/uploads/files/55336354151.pdfIn PDF document text
    • http://basketaci.cz/UserFiles/File/11206630194.pdfIn PDF document text
    • http://ciaomamma.hu/editor_up/wupuru.pdfIn PDF document text
    • https://iohrp.org/f_files/files/duvurudulapolofi.pdfIn PDF document text
    • http://kwiatmetal.pl/userfiles/file/dokikepibepumero.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/15302268904.pdfIn PDF document text
    • http://studiodabo.eu/userfiles/files/juxedamusizetozalizagi.pdfIn PDF document text
    • https://specialgarden.ro/userfiles/file/lexadelufivofusigovuf.pdfIn PDF document text
    • http://ingpoggi.eu/userfiles/files/17859064869.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/92873824113.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137a15cf0f48---fefesevaxik.pdfIn PDF document text
    • http://www.fishandcosolicitors.com/uploads/files/wurutuxemezeros.pdfIn PDF document text
    • http://newbusan.net/FileData/ckfinder/files/20210902_C756A23723003653.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_off0000c493.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC493 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCA5 18500 bytes
SHA-256: 8fbe40f489d7d154dcb2ed91ba4860d9f38df08d9695d89a6d2da6e81327e892
font_02_sfnt_off00010ce9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE9 11080 bytes
SHA-256: 73d23c0fac50635749eb09f5668ae539ea74a1d1eb71d35e8205a55a4a84abbe