Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c38dd7fb6dc7c2b…

MALICIOUS

PDF

88.5 KB Created: 2021-04-20 05:36:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-04
MD5: 67eabdd19664ec5fa870f1c645a88f3d SHA-1: b60cf5766681392b0e11fbdbde43c260aaf0f21a SHA-256: 3c38dd7fb6dc7c2bf4b55a87a255877f385693c15ed9e9ead3befdb2214bfbdb
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to link farms hosted on disposable domains, suggesting an attempt to obscure the final malicious destination. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a strategy of using many distinct hosts to distribute links, a common tactic for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://russian-ice-spb.ru/sites/default/files/webform/files/40307308503.pdf In PDF document text
    • https://aboss.by/sites/default/files/webform/pibodanagulevegomenet.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/setafemamuf.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/28911573484.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/vetasitumuwogemukuruv.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/sojivezogi.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/6948618973.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/22435641867.pdfIn PDF document text
    • https://grossenbacher.co.nz/en/system/files/avoidance-training-certificates/tojawi.pdfIn PDF document text
    • http://klm3fg.grhosting.cz/sites/default/files/webform/files/5308316073.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/natogaj.pdfIn PDF document text
    • http://www.guninetwork.org/system/files/webform/heirri_proposals/74543186253.pdfIn PDF document text
    • http://portal-mysigma.com/system/files/student-proof/41429692510.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/99469138220.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/79062027218.pdfIn PDF document text
    • https://www.mothercare.ro/sites/default/files/webform/resumes/xigidaz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=partituras+de+canciones+cristianas+para+piano+gratisPDF link annotation
    • https://gradfutures.princeton.edu/system/files/webform/ninavixokamorul.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/5272012193.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010a46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A46 3312 bytes
SHA-256: 082c89522e4251f0a814862fddf633b1dac669eb780a02580130c1f52bfffe84
font_01_sfnt_off00011627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11627 5208 bytes
SHA-256: 36571e0e1bfa83077e3eb46a46b65ea5404f7f0bd24523dd07d5b119a6108aa9
font_02_sfnt_off000127ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127ED 13112 bytes
SHA-256: 3561dc1723e517e485651ce8c732c452e370d071759ee8638055f69535e8a7f3