Malicious PDF — malware analysis report

Static analysis result for SHA-256 5237b4c1d096babd…

MALICIOUS

PDF

81.3 KB Created: 2021-09-10 20:09:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: bb9732fe58febeb9f4331db81cf0d485 SHA-1: 5796bcd2f6995743da87f79a73791d7203175f6c SHA-256: 5237b4c1d096babdb7046144c26231bb77127382562cf5a98530c5edc8c6755a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs pointing to disposable domains, identified as a link farm, suggests a phishing or malware distribution scheme. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://world-spa-resorts.com/dok/2026469185.pdf In PDF document text
    • http://mayinmaunhat.com/upload/files/vagilijijevisisarutezajo.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/tupax.pdfIn PDF document text
    • http://cmorshomecareassociates.org/uploaded_files/userfiles/files/22828834911.pdfIn PDF document text
    • http://crystal-lamp.ru/uploads/files/gefuwumofuri.pdfIn PDF document text
    • http://akcjonariusz.com/UserFiles/file/2418032784.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/161333d9d9be58---53891461626.pdfIn PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/kafaji.pdfIn PDF document text
    • http://toszegisuli.hu/userfiles/file/tabakilugeguxibo.pdfIn PDF document text
    • http://cuathepvangohaiduong.com/images/ckeditor/files/zuxezas.pdfIn PDF document text
    • http://globomax.eu/userfiles/file/furemekitisolerubu.pdfIn PDF document text
    • http://cmrivestimenti.com/userfiles/files/14984303695.pdfIn PDF document text
    • http://bubb.cn/up_file/file/33148111528.pdfIn PDF document text
    • https://omprintandpack.com/userfiles/file/8443052323.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b24027f47f---6005600033.pdfIn PDF document text
    • https://mangonebike.com/uploads/file/14800125146.pdfIn PDF document text
    • http://tunapvietnam.thietbiotoviet.com/Images_upload/files/56943340211.pdfIn PDF document text
    • http://tcgardening.com/userfiles/file/2021090212055773499.pdfIn PDF document text
    • https://people11people.gr/uploads/File/zasigomezefun.pdfIn PDF document text
    • http://www.anaja-inter.org/public/file/94735964222.pdfIn PDF document text
    • http://avision-italia.com/userfiles/files/1948637023.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=aplikacja+do+rozpoznawania+piosenek+androidPDF link annotation
    • https://rt9.rspo.org/ckfinder/userfiles/files/biwesejivuvafubawokiz.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_off0000d82b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD82B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f03d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF03D 18540 bytes
SHA-256: 7a5a4e903bcb48c37f516864514bdedba5a74b7bec30e74be420a88e43305774
font_02_sfnt_off00011ed2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11ED2 10760 bytes
SHA-256: 04054a87d49b067c48b9fd242b0af7d83ad1312635d1e715ccb9c38ec798cd56