Malicious PDF — malware analysis report

Static analysis result for SHA-256 271c4623a1c26c61…

MALICIOUS

PDF

80.8 KB Created: 2021-09-16 12:26:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 818ff535e7e5bdadd5f6e24418c7a34d SHA-1: 3cdd46b70cc1bc41536cb7b571cc1949b9725f16 SHA-256: 271c4623a1c26c6157c1baca94a2497cf9dda72da1b0f09ae4418a8a139da79c
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to numerous disposable domains, several of which are hosted on compromised CMS upload storage. The embedded URLs suggest a tactic to obscure the true destination and potentially evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://ariogalospspc.lt/userfiles/file/2340924990.pdf In PDF document text
    • https://biserica-izvorul-tamaduirii.ro/files/roxiwutetezizerudopa.pdfIn PDF document text
    • https://omnistopbollards.com/application/third_party/ckfinder/userfiles/files/nopiwi.pdfIn PDF document text
    • http://osstemcardiotec.com/files/fckeditor/file/740011629613feb4da59b4.pdfIn PDF document text
    • http://mnarch.it/userfiles/files/28054638353.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/jcl178gnejlj6h725kk469u30p/pogiriwudavipaf.pdfIn PDF document text
    • http://velomagazin.hu/UserFiles/file/ditubinub.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bd1f20fee6---18017249754.pdfIn PDF document text
    • http://bekkercoon.ru/ckfinder/userfiles/files/29789513741.pdfIn PDF document text
    • http://clearspace-design.com/CKEdit/upload/files/bipuzapenapozit.pdfIn PDF document text
    • http://agecarekorea.com/ckupload/files/bekarija.pdfIn PDF document text
    • http://www.la-rocca.pl/app/webroot/files/files/93470640257.pdfIn PDF document text
    • http://pebyte.com/wp-content/plugins/super-forms/uploads/php/files/t3skt58bnl8u5u4t742un6sbg1/bedepowelujakipojiregigaw.pdfIn PDF document text
    • http://eiffelflowersquesnel.com/userfiles/file/xirifowonoz.pdfIn PDF document text
    • https://www.taxikladis.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16133d3d57bf1a---94336084031.pdfIn PDF document text
    • https://media-get.ru/userfiles/files/xuguk.pdfIn PDF document text
    • https://alpasol.e-giant.net/upload/files/45489003339.pdfIn PDF document text
    • https://ms02bet.com/contents/files/dixor.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16134cff12c867---xovotifowujopeke.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/77a16831e047a9d737b880271ce2cfd1/69716510051.pdfIn PDF document text
    • http://pileshoppen.dk/userfiles/file/dipojelefusepezegi.pdfIn PDF document text
    • http://synphabase.ch/upload/file/48886566546.pdfIn PDF document text
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/ligoxorupezomujamogagof.pdfIn PDF document text
    • http://barefoot.pl/userfiles/file/bilowuzovup.pdfIn PDF document text
    • http://profesniprukaz.cz/ckfinder/userfiles/files/xidix.pdfIn PDF document text
    • http://jsdarvin.com/files/80599037604.pdfIn PDF document text
    • https://livstyle.ro/home/livstyle/public_html/uploads/files/darelonizogomawobeb.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/64989866624.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=the+best+car+racing+games+for+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_off0000d80e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD80E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f020.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF020 17012 bytes
SHA-256: f5ec9fd84d50664f0e40cf38c9fdcb63bbcedd955ff1d559e38a78705544d00f
font_02_sfnt_off00011c15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C15 10980 bytes
SHA-256: f4f6d1830b08807fa37913a0b9ac1d78b60722368ca7ec377c0d8a7e50fc6596