Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4a5b5250ab90427…

MALICIOUS

PDF

85.9 KB Created: 2021-09-16 03:06:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-07
MD5: 6d1186df350c39eca373e6a42a28bb82 SHA-1: 85563c24994573ae85918ba8fd0e6d7988f6b726 SHA-256: f4a5b5250ab9042767c5eca4daaaa39132045957b48fa977f7e31a2b94d59162
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It contains a large number of external URIs, many of which are hosted on disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics point towards an attempt to lure users to external sites, likely for credential harvesting or further malware delivery.

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://crewmak.ru/uplcv?utm_term=assets+for+android+app PDF link annotation
    • http://nsmpublicschool.org/slbdavbatala/userfiles/file/42980582087.pdfIn PDF document text
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/3fe5328a9c336770d7c74545fc6ecf95/29297208323.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/valetorotuwowe.pdfIn PDF document text
    • https://viboot.com/ckfinder/userfiles/files/dipabofuxunozokugero.pdfIn PDF document text
    • https://jphotographyllc.com/userfiles/file/vexiwotenexatu.pdfIn PDF document text
    • http://e-skala.pl/userfiles/file/vabalusepixifadixu.pdfIn PDF document text
    • https://zivotzaokny.eu/res/file/2868567467.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/wojef.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/zuxulijeluni.pdfIn PDF document text
    • https://gangwontaxi.com/FileData/ckfinder/files/20210915_62980D9138E3A88A.pdfIn PDF document text
    • http://dellalontra.it/userfiles/files/59067506879.pdfIn PDF document text
    • http://sun-eko.eu/files/file/mowagituwome.pdfIn PDF document text
    • http://xn--b1adcbbai1bezln.xn--p1ai/content/File/guxifesa.pdfIn PDF document text
    • http://jrmhandling.nl/upload/file/666735995.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/10023731919.pdfIn PDF document text
    • https://www.sibirprokat.ru/ckfinder/userfiles/files/65161004713.pdfIn PDF document text
    • http://hitplus.eu/userfiles/file/xapedezagowanu.pdfIn PDF document text
    • http://geteffective.biz/uploadfiles/file/34816983467.pdfIn PDF document text
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613d8b7160b63---vozem.pdfIn PDF document text
    • https://cafesca.org/ckfinder/userfiles/files/zogasuxerupuxanivetigafam.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/webikawe.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/sojasudonemubesazixekiz.pdfIn PDF document text
    • https://estduquebec.com/scripts/php/xenocode/lib/ckfinder/userfiles/files/pafefisipa.pdfIn PDF document text
    • http://babamoleskine.com/files/file/wukabunupelisome.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_off0000edf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF2 10428 bytes
SHA-256: 4a6e309c8a6cfb525669389c6c28b381a99a025bd5a8c0578b38c58c2c0ebc39
font_01_sfnt_off000105b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B4 17180 bytes
SHA-256: 8c62a1cbed4e5be227a767e9447494cf22492e3b006fc526cd3b0affbcfb3aa7
font_02_sfnt_off00013206.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13206 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1