Malicious PDF — malware analysis report

Static analysis result for SHA-256 937dceb6c1ea8628…

MALICIOUS

PDF

72.4 KB Created: 2021-09-25 07:48:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7e0629e7abb332da21ea315b832cb704 SHA-1: 8b17fe6662384235f15f0711941b4eda78f52f7b SHA-256: 937dceb6c1ea86281868347588bac90cd11addff5222b9dd11638b4c96db5ec2
126 Risk Score

Malware Insights

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

The PDF was flagged as malicious by ML classifiers and ClamAV. It contains numerous embedded URLs pointing to various domains, with a significant heuristic indicating it's a link farm on disposable hosting. The primary malicious URL identified is http://chukysovin.com/img-svc/files/wutasibijarinorizanu.pdf, which is likely used to distribute further malicious content or phish users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://chukysovin.com/img-svc/files/wutasibijarinorizanu.pdf In PDF document text
    • http://konikanarrowfab.com/ckfinder/userfiles/files/tikafozogop.pdfIn PDF document text
    • http://tid.vn/upload/files/gepuworubosugan.pdfIn PDF document text
    • http://sperrincaravans.com/images/file/muwijujalulagizekazarip.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c2d5e92e3e---bagewivunaper.pdfIn PDF document text
    • https://khonggiansangtao.com/platformecom/img/upload/file/jewifezavuwemexek.pdfIn PDF document text
    • http://arc-en-cielproduce.com/ckfinder/userfiles/files/33317553199.pdfIn PDF document text
    • https://sellos-mecanicos.com/wp-content/plugins/super-forms/uploads/php/files/6efadcbb5c9c56e7954132958c2f1d5a/titejaf.pdfIn PDF document text
    • http://muacuoi.vn/Pictures/files/7450516399.pdfIn PDF document text
    • http://status-go.net/gfx/userfiles/files/54426560904.pdfIn PDF document text
    • https://evrenmentese.com/upload/ckfinder/files/gojalalugakozamejewizijev.pdfIn PDF document text
    • http://ssaisarang.com/ckfinder/userfiles/files/75515354743.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/80197799906.pdfIn PDF document text
    • https://minhkygroup.com/luutru/files/95870871197.pdfIn PDF document text
    • http://hzqzg.com/d/files/betilitazatisal.pdfIn PDF document text
    • https://lescourailleurs.com/upload/editor/file/sowetalejudolenesolulu.pdfIn PDF document text
    • http://imcborivali.org/userfiles/file/xakuvam.pdfIn PDF document text
    • http://smsgurugram.com/miet/assets/files/gimawugavesuruliwewabexa.pdfIn PDF document text
    • http://www.workbythai.com/admin/assets/images/losagazupuwi.pdfIn PDF document text
    • http://imaginove.eu/data/Files/devegidetinuwu.pdfIn PDF document text
    • http://phuquytravel.com/nguyenvanlinh/files/16978901244.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/sonidem.pdfIn PDF document text
    • https://viktorina.ledoritulys.lt/files/82084980831.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+compress+an+image+on+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_off0000b3f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB3F2 17652 bytes
SHA-256: 18dcff7f498fbd9b332a0d836f8fb4f63946851f38bc9251513cb5d1bbf17a63
font_01_sfnt_off0000e0c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0C7 10888 bytes
SHA-256: 39514eab36f094e688f3adfa34c40dd49cfbf151d8f0e2fd9af603174458516a
font_02_sfnt_off0000f9c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1