Malicious PDF — malware analysis report

Static analysis result for SHA-256 3933e9a8e3a378e9…

MALICIOUS

PDF

75.6 KB Created: 2021-09-24 06:04:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e4f97b0613fe9b83689e4bc65aa611b5 SHA-1: a8eeac75627860c367056989554b2b2f8d018932 SHA-256: 3933e9a8e3a378e96d550e90ba6e067e734c641e051265d3218796630ed94173
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple domains, many of which appear to be compromised WordPress sites or disposable hosting. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM indicate a pattern of using such sites for hosting malicious files. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9901

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://chcial.ru/uplcv?utm_term=ultimate+truck+driving+simulator+2020+download PDF link annotation
    • https://khotelmarket.com/FileData/ckfinder/files/20210913_304D9FE98B8DAE84.pdfIn PDF document text
    • https://thehouseconcert.com/ckfinder/userfiles/files/bipixexoginu.pdfIn PDF document text
    • http://biswasi.com/userfiles/files/40556574702.pdfIn PDF document text
    • http://noithattamphuong.com/upload/files/94604459346.pdfIn PDF document text
    • https://gallerylingard.com/uploads/file/57566024243.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614025406443e---33595826816.pdfIn PDF document text
    • http://iuf.kr/pds_down/files/rubin.pdfIn PDF document text
    • https://gmt-tw.com/app/webroot/userfiles/files/vunaxozaboteguwedu.pdfIn PDF document text
    • https://himalayanespresso.com/espresso_ckfinder/userfiles/files/fosedudodalenukazur.pdfIn PDF document text
    • http://airmon.hu/images/files/mezazexosafufabuxowowamaf.pdfIn PDF document text
    • https://oolong-dining-co.com/webroot/editor-uploads/files/movasaxi.pdfIn PDF document text
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/pesipowaruro.pdfIn PDF document text
    • https://tvsporedi.si/vsebina/99741130265.pdfIn PDF document text
    • https://duragloss.pl/userfiles/file/78081529428.pdfIn PDF document text
    • http://ztracenaexistence.cz/files/content/file/kudovudogalaxa.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/sewijufakisivofe.pdfIn PDF document text
    • https://cityface.cz/res/file/farug.pdfIn PDF document text
    • http://palmdale.thepokeluau.com/uploads/files/52817133009.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f9e389ac1f---69913726056.pdfIn PDF document text
    • http://3e-machinery.ru/app/webroot/filesfiles/57401951.pdfIn PDF document text
    • http://b40555.handyfriendship.com/upload/files/varetefojejaremipuj.pdfIn PDF document text
    • http://www.naturhalles.fr/fckeditor/userfiles/file/17199710219.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/161364904d2273---zamedawagikazexexaxefik.pdfIn PDF document text
    • http://frederickfollows.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613c1c7189995---55951706841.pdfIn PDF document text
    • http://fullx.net/files/31758806289.pdfIn PDF document text
    • https://familienbilstrup.dk/ckfinder/userfiles/files/20548730212.pdfIn PDF document text
    • http://przedszkolenisko.pl/userfiles/file/74566858655.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_off0000c1b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1B4 11308 bytes
SHA-256: bef1a48e8d6d465cdfd2b1ce4073824a58b52696a8ac83dec13e943b51685efc
font_01_sfnt_off0000dc25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC25 17032 bytes
SHA-256: 4a20fb417f3cdebc60962e0ac48a832e383a4832a4638fb06839793c5a7cbac2
font_02_sfnt_off0001082e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1082E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1