Malicious PDF — malware analysis report

Static analysis result for SHA-256 83a9322aa8c45bfa…

MALICIOUS

PDF

84.5 KB Created: 2021-10-06 20:24:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 83a4d4e19d976474ab1567dfa812a548 SHA-1: e29ed2caf12defff7ee3a8c460b33713194d6e86 SHA-256: 83a9322aa8c45bfa5576d14b4b5fa2a901d7858747f229392ef5cea2744fb824
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, specifically identified as a phishing trojan. It contains numerous embedded URLs pointing to compromised websites and disposable hosting, suggesting a link farm designed to redirect users. The PDF structure and embedded content indicate it's likely part of a phishing campaign or serves as a downloader for further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://coretry.ru/uplcv?utm_term=radiographer+working+hours PDF link annotation
    • http://huemin.com/fckeditor/userfiles/file/lonudowefuvorowuribetivag.pdfIn PDF document text
    • http://dhf-china.com/d/files/pugerepetipixa.pdfIn PDF document text
    • http://delta-serwis.pl/pliki/tobujirivarorovuta.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/5830753450.pdfIn PDF document text
    • https://studiopros.com/userfiles/file/In PDF document text
    • https://sk-elektron.ru/ckfinder/userfiles/files/33125194051.pdfIn PDF document text
    • https://pokereshop.cz/data/file/79914538827.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613faa66ef730---39153416686.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/kalikuzarasimulader.pdfIn PDF document text
    • http://dkmmotor.com/files/userfiles/file/4253091780.pdfIn PDF document text
    • https://daiichitravel.com/uploads/news_file/paruvix.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613debd1ef540---gavagib.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/48b02aae9dfd6c1b0cf38a7a5d6f42af/68309420122.pdfIn PDF document text
    • http://licausi.it/userfiles/files/8914762862.pdfIn PDF document text
    • http://cyc.cz/pictures/clanky/files/pubujiwidowodagojupemap.pdfIn PDF document text
    • https://curvy.tw/upload/files/nobinofuwenumeve.pdfIn PDF document text
    • http://gabinetpro.gabinetpro.pl/kosmetyczka/krakow/files/87643586995.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/55077380620.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/14532588307.pdfIn PDF document text
    • https://sensiblemachines.com/ckfinder/core/connector/php/files/86721390764.pdfIn PDF document text
    • https://verlauf-ekb.ru/admin/ckfinder/userfiles/files/23586816982.pdfIn PDF document text
    • http://velapower.com/glwh/UploadFile/file/2021092005155573499.pdfIn PDF document text
    • https://y3stwk65l-mn9.com/contents/files/numexupidukurirokegak.pdfIn PDF document text
    • http://quaisetoiles.fr/img_pages/file/40632782895.pdfIn PDF document text
    • http://dlevitin.ru/fck_editor_files/files/xirozomitekesikuvolapuxo.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_off0000e11f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE11F 10848 bytes
SHA-256: b0fc2a25d4f299e98907e8ba3316b4e70a9f0740ec9e10e0adf1193138f10d10
font_01_sfnt_off0000f9ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9ED 19156 bytes
SHA-256: c3e7b0d38725ac59db0392bc5568284807db92d3b73ba8499e35512b9d6756b2
font_02_sfnt_off00012c32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1