Malicious PDF — malware analysis report

Static analysis result for SHA-256 e5f9a7fcbe951e9a…

MALICIOUS

PDF

83.1 KB Created: 2021-09-19 15:03:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c700331d0bf7aea0093bf0db59a4ff08 SHA-1: cbd035c3bbbe125917a0db3db3bd0c437009a8d3 SHA-256: e5f9a7fcbe951e9a83c8e58f92e3c8af71a174b8e7c129c610c6b85fab94de52
126 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous external URIs and is identified as a link farm hosted on disposable domains, suggesting it's designed to redirect users to potentially harmful websites. The document body is heavily obfuscated, preventing analysis of its specific content, but the overall structure and heuristic firings point towards a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://medvor.ru/uplcv?utm_term=android+draw+signature PDF link annotation
    • http://ipceurope.be/assets/file/37229345783.pdfIn PDF document text
    • http://honderhotel.com/UploadFiles/FCKeditor/20210904184634.pdfIn PDF document text
    • http://ancheng-medical.com/uploadfile/files/61920999068.pdfIn PDF document text
    • http://mwbright.com/upload_fck/file/2021-9-1/20210901131749130697.pdfIn PDF document text
    • https://stealthwindow.tw/uploads/files/202109121524412313.pdfIn PDF document text
    • http://solarexperte.ch/fckeditor/editor/images/file/tigukogamugig.pdfIn PDF document text
    • http://xn--80aikni6a0b.xn--p1ai/images/file/54404876365.pdfIn PDF document text
    • https://ladangmimpi2.com/contents/files/liwabodur.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/fulowolirovuji.pdfIn PDF document text
    • http://uklearningnetwork.com/userfiles/file/tizonujaxinas.pdfIn PDF document text
    • http://jamoncup.es/wp-content/plugins/formcraft/file-upload/server/content/files/161433dca523cd---vuterevepen.pdfIn PDF document text
    • http://hp-cnc.de/uploads/files/punivolavoz.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/51845485279.pdfIn PDF document text
    • http://kengosushionlineorder.com/uploads/files/kisidunavesagelub.pdfIn PDF document text
    • http://watdoenwevandaag.nl/upload/75541580921.pdfIn PDF document text
    • http://gbfrjournal.org/pds/userfiles/files/tuzujesisojuxepime.pdfIn PDF document text
    • http://canoeing.by/pics/files/22899224922.pdfIn PDF document text
    • https://strings97.hu/userfiles/file/46089805106.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/58113725691.pdfIn PDF document text
    • http://jinwoosmc.com/userfiles/file/bibazukexawibidebewus.pdfIn PDF document text
    • http://sowa-architekci.pl/userfiles/files/51795011533.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/29296060495.pdfIn PDF document text
    • http://abwclayton.com/uploads/files/71789416199.pdfIn PDF document text
    • https://tselectromechanical.com/uploads/CKfiles/files/73819605993.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_off0000ddb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB1 18496 bytes
SHA-256: 49f800c09b63fa4f5dbb80c6eeacda8c3f3918c3e1a7f9431332016d95b1bbd9
font_01_sfnt_off00010ea7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA7 10544 bytes
SHA-256: cac64594cd7bfd36e91f385acc3ace834791ef2fcae475e0843bbcfe1fc51ce8
font_02_sfnt_off000126b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1