Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3c7a2c18c12294c…

MALICIOUS

PDF

79.8 KB Created: 2021-09-19 01:50:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4a206b4e40d965a01d18d70900ee3719 SHA-1: 9cbd0f64fef7b4eec673a61b9c103bd3d6f171c7 SHA-256: b3c7a2c18c12294c00f501d48f7a66c2ef0b9e9615418af177b22f68c509a199
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and configured as a link farm, suggests a phishing or malware distribution scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically highlights this behavior, indicating the PDF's purpose is to redirect users through a chain of links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://nfc-lampang.com/user_img/files/zojapobefikaviva.pdf In PDF document text
    • http://abwjefferson.com/uploads/files/6318181444.pdfIn PDF document text
    • https://g55net.com/webpagebuilder/ckfinder/userfiles/files/zamafizovano.pdfIn PDF document text
    • http://bangdinhphucat.com/quangbasanpham/app/webroot/upload/image/files/37092407366.pdfIn PDF document text
    • https://yesilkoyluleriz.biz/resimler/files/nofev.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/2021912149213732.pdfIn PDF document text
    • https://willmarareachamber.com/ckfinder/userfiles/files/2601493046.pdfIn PDF document text
    • http://5lovestartw.com/CKEdit/upload/files/59783481867.pdfIn PDF document text
    • http://alpes-maritimes.proximeo.com/ckfinder/userfiles/files/vokofubulogibugelugobe.pdfIn PDF document text
    • http://sangjeom.com/userfiles/file///17898551101.pdfIn PDF document text
    • http://polipack.ru/content/file/debikuvowepejubovike.pdfIn PDF document text
    • http://prvugkh.ru/uploads/files/wibusesurokiparunu.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/88158515668.pdfIn PDF document text
    • http://morpheus-architects.com/file_media/file_image/file/fezulagodi.pdfIn PDF document text
    • https://www.wizzfizz.com.au/application/third_party/ckfinder/userfiles/files/tewegazosafilo.pdfIn PDF document text
    • http://fcraregistration.com/UploadedData/file/vurebukalutifejofisu.pdfIn PDF document text
    • https://phucatgarment.com.vn/ckfinder/userfiles/files/pajokezaluzivadaxe.pdfIn PDF document text
    • https://krajkarka.cz/userfiles/file/rikevozeliwefawapu.pdfIn PDF document text
    • http://btfa.tw/upload/files/direnakifugugenuvabowu.pdfIn PDF document text
    • http://unitec-egypt.net/userfiles/file/800418999.pdfIn PDF document text
    • https://mccartha-cobb.com/userfiles/files/tikamosisezufuvupum.pdfIn PDF document text
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/arsvhu8vbbrk095mcm4rd3ji4u/nuwevo.pdfIn PDF document text
    • http://adriennemason.com/assets/files/35792956328.pdfIn PDF document text
    • https://eol.org.pe/ckfinder/userfiles/files/54878319517.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=move+itunes+music+to+androidPDF 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_off0000d4df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4DF 10644 bytes
SHA-256: a14be2915e0b2f0a7d7604005b167d0827f75bcd4c48764c242d36d28f81891d
font_01_sfnt_off0000ed4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001055f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1055F 17304 bytes
SHA-256: 5f34f3dddd24d3688e91c138c5ac33bd0b9c19ac2894ea126f90a0c4b8ca4217