Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a7381aaff2fb085…

MALICIOUS

PDF

86.9 KB Created: 2021-09-13 19:27:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 25e1eaeeabcc8a1e35427b679d3462fe SHA-1: 0d41c222bdd240441d93ef053365c79031d09872 SHA-256: 1a7381aaff2fb085d27b7bca787feab5c08c2acb1bd7b18beb8b1070d9c61680
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains numerous embedded URLs pointing to disposable hosting, indicating a link farm designed to redirect users to malicious sites. While no scripts were explicitly extracted, the PDF structure and the presence of many external URIs suggest an attempt to exploit users through deceptive links, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://coretry.ru/uplcv?utm_term=the+secret+history+of+the+world+pdf PDF link annotation
    • http://hftyby.com/upload_fck/file/2021-9-3/20210903084739448030.pdfIn PDF document text
    • https://krainaogrodow.eu/zdjecia/fck/file/97836091784.pdfIn PDF document text
    • http://fuerst-architects.com/uploads/file/66903086621.pdfIn PDF document text
    • http://nakloboucku.cz/uploaded/file/93112484111.pdfIn PDF document text
    • http://ap116.ru/userfiles/file/16718350569.pdfIn PDF document text
    • http://victoryelectricalsupply.com/ckfinder/userfiles/files/77278852078.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16132da867ed7f---nezen.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/e1719cd9fdc5b3a74cc08abccd6a81b6/42489774023.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/92945378839.pdfIn PDF document text
    • https://egyediajandekotletek.hu/mvc/userfiles/file/30977772452.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210903105621.pdfIn PDF document text
    • http://thuexe7cho.vn/upload/files/35635026439.pdfIn PDF document text
    • http://forspeed.cz/ckfinder/userfiles/files/pifibinawoxunuzuzax.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/13771785499.pdfIn PDF document text
    • http://ciarajewellery.com/editor_upload/file/zamilafugi.pdfIn PDF document text
    • https://xn--z4qq44i.xn--kpry57d/upload/actfiles/12886924264.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/pijekebivokenobegiv.pdfIn PDF document text
    • http://mygotour.com/FileData/ckfinder/files/20210903_0F50A4851BD42719.pdfIn PDF document text
    • http://arcadia-fitness.es/userfiles/file/venemikesakatame.pdfIn PDF document text
    • http://xn----7sbakif2a3azdub.xn--p1ai/admin/ckfinder/userfiles/files/6250621017.pdfIn PDF document text
    • https://ooobelkom.ru/ckfinder/userfiles/files/sisugobidoziwometo.pdfIn PDF document text
    • http://akwarella.pl/user_uploads/file/zekupekavefifuvo.pdfIn PDF document text
    • http://tolaniprojects.com/userfiles/file/48690204515.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_off0000ec76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC76 18668 bytes
SHA-256: 563ac44b170d08d8d89cce65d7adfb0886cd2abdfa3d9f198a424e1c42330b14
font_01_sfnt_off00011d11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D11 10612 bytes
SHA-256: d0bb6d77580f16c6781b0d4e192bd3bbe599af7f8c7da7542298142b6e9570c2
font_02_sfnt_off0001358d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1358D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1