Malicious PDF — malware analysis report

Static analysis result for SHA-256 4275ee9560f21838…

MALICIOUS

PDF

83.1 KB Created: 2021-09-17 05:20:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 1cb74c512732d044accbd14457eaa16a SHA-1: 362bf32dc4dd5a62bd38db569eed74858c62706e SHA-256: 4275ee9560f21838be34d531d8c4cfc470f5a6f3c82301844b78e456408c729a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of embedded URLs, many of which point to disposable hosting or are part of link farms, indicating a strong likelihood of phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external links suggest an attempt to redirect users to malicious content, potentially leveraging embedded JavaScript for obfuscation or execution.

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://archism.ru/uplcv?utm_term=stunning+in+spanish+language PDF link annotation
    • https://przyklejki.pl/userfiles/42147881239.pdfIn PDF document text
    • https://tectrongim.com/uploads/file/vusevevimazuxozobafa.pdfIn PDF document text
    • http://acudrved.com/ckfinder/userfiles/files/perokaturediwumewawipo.pdfIn PDF document text
    • https://archcosmeticstudio.com.au/wp-content/plugins/super-forms/uploads/php/files/64062ecad7b19aca043bbdbc5d893733/3910404740.pdfIn PDF document text
    • http://linyuepharm.com/upload/files/60361492794.pdfIn PDF document text
    • http://aburobocon2019.mnb.mn/uploads/files/33529648471.pdfIn PDF document text
    • http://savemaxint.com/files/file/lexobab.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/20406572410.pdfIn PDF document text
    • http://ulrike-mayer.de/userfiles/files/bexegusubisexutuwopubutal.pdfIn PDF document text
    • https://quatden.vn/webroot/img/files/86864021609.pdfIn PDF document text
    • http://year-c.com/upload_fck/file/2021-9-14/20210914102319402020.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1613627994875c---53120120633.pdfIn PDF document text
    • http://gyermekhaz.hu/Content/site_images/files/bisotomilozajonizu.pdfIn PDF document text
    • http://chupanhnoithat.vn/upload/files/miberejisitowi.pdfIn PDF document text
    • http://s2ipower.com/survey/userfiles/files/fotiritulidizuvumifonovi.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/26371387725.pdfIn PDF document text
    • http://chugguwang.com/files/fckeditor/file/sibew.pdfIn PDF document text
    • http://yas-center.ru/userfiles/file/megesugekitepunof.pdfIn PDF document text
    • http://spad.kr/userData/ebizro_board/file/jidedadofuzos.pdfIn PDF document text
    • http://dalnoboy.net/data/filestorage/upload/files/luneluvajufutopatis.pdfIn PDF document text
    • http://www.bandungmesin.com/file/nevolenujekokux.pdfIn PDF document text
    • http://stigstudiotecnico.it/userfiles/files/84750086919.pdfIn PDF document text
    • https://rh-h1tapi-turbo.com/contents/files/pekavijanixomilumuzike.pdfIn PDF document text
    • https://educhina.mn/editor/files/2882409548.pdfIn PDF document text
    • http://smingames.com/ckfinder/files/vopaja.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_off0000de75.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE75 10488 bytes
SHA-256: 6777ced08023cef70e799eec6bbecb3cbff2657e9bbdf214296b1211aa501ca9
font_01_sfnt_off0000f635.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF635 18424 bytes
SHA-256: df9cd06ddfd36b5098e5ad294f5c5e8532457c8891250a92a5644624746881b8
font_02_sfnt_off000126e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x126E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1