Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec4f90d27e2ee930…

MALICIOUS

PDF

78.4 KB Created: 2021-09-24 12:36:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 349d2de1247a92bf06de7542317a346f SHA-1: c7abb2bdc43bb678c21b954f65cfbf945cb27f09 SHA-256: ec4f90d27e2ee93077cd0df381c55b974521e9b6b3fb00298b40750a82161cf5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is part of a link farm designed to distribute content from disposable hosting. The embedded URLs point to various PDF files, reinforcing the idea of a distribution network. Although no scripts were explicitly extracted, the nature of the link farm and the malicious verdict suggest it may contain embedded JavaScript or exploit code to redirect users or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://noxsun.com/jingkelun/userfiles/files/20210910035618.pdf In PDF document text
    • http://cukorbetegshop.hu/files/gazuravi.pdfIn PDF document text
    • https://balajihighfields.in/userfiles/file/woloxe.pdfIn PDF document text
    • https://senzedigicraft.com/wp-content/plugins/super-forms/uploads/php/files/cd7c2c8a9f4399e881fd1bfe3e36f161/69047182889.pdfIn PDF document text
    • https://xenang-mitsubishi.com/fckupload/file/45440542652.pdfIn PDF document text
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/mejaruvokosodobejusi.pdfIn PDF document text
    • https://bleikss.com/userfiles/file/nafopewirigen.pdfIn PDF document text
    • https://valstybestarnyba.com/upckfinder/files/57305366320.pdfIn PDF document text
    • http://kondicionery-vidnoe.ru/upload_picture/file/19837582101.pdfIn PDF document text
    • https://aurorabersinar2.com/contents/files/lotojefopopet.pdfIn PDF document text
    • http://gevenschoenen.nl/ckfinder/userfiles/files/vujitutesosanamufibar.pdfIn PDF document text
    • https://proartgaleria.hu/files/files/sekotemuwu.pdfIn PDF document text
    • http://wxdyzs.com/userfiles/files/suwetigovunidazorukesowew.pdfIn PDF document text
    • http://sjar-tech.com/uploadfile/file///2021091804465345.pdfIn PDF document text
    • https://zahrek.com/userfiles/file/zumeregemekamidubezok.pdfIn PDF document text
    • https://aznamaste.com/ckfinder/userfiles/files/wuguwaxiwal.pdfIn PDF document text
    • https://12shio2.com/contents/files/nekubetisirexurafesi.pdfIn PDF document text
    • http://studiomilano.eu/userfiles/files/kagajad.pdfIn PDF document text
    • http://residencelesaline.it/userfiles/files/81998188911.pdfIn PDF document text
    • https://www.wikiwebagency.it/wp-content/plugins/super-forms/uploads/php/files/829401c82d80e4d6f4026c17dba851ed/redakomelijakukul.pdfIn PDF document text
    • http://naoshima-tours.com/images/blog/file/58276539326.pdfIn PDF document text
    • http://spartaksedlec.cz/spartaksedlec/userfiles/file/jugidexivir.pdfIn PDF document text
    • http://jsdarvin.com/files/zakukavudituveli.pdfIn PDF document text
    • http://pc-driver.ru/userfiles/files/13748553742.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=bus+simulator+mod+apk+hackPDF link annotation
    • 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_off0000ccfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCFC 17948 bytes
SHA-256: 5ae2bd3593d2ba7bee1e11e92ccab13d357ec9f5185e092a364e03f5d3c164f4
font_01_sfnt_off0000fb61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011378.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11378 10788 bytes
SHA-256: 6b6feffc1f27a19606d7fdc9ca4c760b6d5e1ac7ed4847eb761673406b5c5371