Malicious PDF — malware analysis report

Static analysis result for SHA-256 2bbfdd781a477773…

MALICIOUS

PDF

88.7 KB Created: 2021-10-11 11:45:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 69d95beeabf072a850f46e1051ffdce2 SHA-1: 21ee2e134635b1671ae98be8b49a6720ce132b30 SHA-256: 2bbfdd781a477773c11ee0f5f801774ced9290a6049c6bfa9cb43b9630a72a22
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, with one specifically pointing to 'smidgel.ru' and a query parameter suggesting a lure for game downloads. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using multiple disposable domains for link farming, reinforcing the phishing or malware distribution intent. While no scripts were explicitly extracted, the presence of external URIs and the link farm nature strongly suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9764

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://smidgel.ru/uplcv?utm_term=fnaf+2+download+free+full+android PDF link annotation
    • http://studiotecnicomancini.eu/userfiles/files/71143341662.pdfIn PDF document text
    • https://blv.by/upload/editor/files/80703851956.pdfIn PDF document text
    • http://universalgroupautos.com/files/others/44070893996.pdfIn PDF document text
    • http://gardatrans.com/content/Files/fibixazoz.pdfIn PDF document text
    • https://tarsiman.ee/files/file/muxibixufamemetunoga.pdfIn PDF document text
    • https://mcsfood.com/images/file/ponawilutasugoruwis.pdfIn PDF document text
    • http://ibookingkr.com/FileData/ckfinder/files/20210916_23AD5ADA7405F50B.pdfIn PDF document text
    • http://acm-medicali.it/userfiles/files/paguze.pdfIn PDF document text
    • https://mkontakt.pl/dat/file/89247970653.pdfIn PDF document text
    • http://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/jugikasibuwipelireru.pdfIn PDF document text
    • http://rudolphalexander.com/uploads/files/64558249588.pdfIn PDF document text
    • https://gospel-streams.com/asset/ckfinder/userfiles/files/28133322423.pdfIn PDF document text
    • http://saltokisport.com/uploads/files/fedinemeluropefizu.pdfIn PDF document text
    • http://sous-mama.org/userfiles/file/tilezonij.pdfIn PDF document text
    • http://beming.com/ressource/site-image/files/25913140035.pdfIn PDF document text
    • https://www.ocnistudio.cz/ckfinder/userfiles/files/65050062741.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/73213504073.pdfIn PDF document text
    • http://cherriestattoo.com/ckfinder/userfiles/files/19193329898.pdfIn PDF document text
    • http://solarhomepage.ch/fckeditor/editor/images/file/28848398376.pdfIn PDF document text
    • http://chongthamnguoc.vn/img/files/44162406530.pdfIn PDF document text
    • http://ediljolli.com/userfiles/files/27721273796.pdfIn PDF document text
    • http://fields-on-earth.com/images/blog/file/58412782616.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/42826721416.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/21ee221276b109ca6457ccc2df5182a4/98091869050.pdfIn PDF document text
    • http://elsped.hu/files/file/jifulibuwur.pdfIn PDF document text
    • https://lesura.net/userfiles/file/2600069576.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dbe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBE7 10364 bytes
SHA-256: bc6b68a7b61d3cddb84c0f428e581396c9d0c27850aa6c672c319024c5af5c59
font_01_sfnt_off0000f37a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF37A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010b8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B8B 16684 bytes
SHA-256: 5786d7639d2cc1522a1a3889fae5b5c9fbcbd5f5c9de2f5a2930a0e54327038d
font_03_sfnt_off00012324.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12324 18908 bytes
SHA-256: 028103add3a08fffe823f502b15f8f185d92bad6f349a1c0672e275445d0660e