Malicious PDF — malware analysis report

Static analysis result for SHA-256 8abb07b35bbb12f3…

MALICIOUS

PDF

72.6 KB Created: 2021-09-26 23:55:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 9292f89088ef69ca478b32cab33ff193 SHA-1: d9a79fe251a513e13d0225f14a31fb87328aba43 SHA-256: 8abb07b35bbb12f3e99a0bf2310d03ad3319518979d9ee79f4dcc9f6d69799eb
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and is flagged as a link farm on disposable hosting, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to trick users into downloading further malicious content via the embedded links. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with common phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9915

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://chcial.ru/uplcv?utm_term=tom+mitchell+machine+learning+solutions+chapter+3 PDF link annotation
    • http://quatanggiabao.com/images/uploads/files/980151630.pdfIn PDF document text
    • https://interior-mark.com/ckfinder/userfiles/files/virarudewoxoneka.pdfIn PDF document text
    • http://dunajecbiala.pl/upload/File/25473912636.pdfIn PDF document text
    • https://pamukoglu.com/userfiles/file/97559011699.pdfIn PDF document text
    • https://heart-calligraphy.com/uploads/files/202109081745039655.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/38310893641.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/14369368129.pdfIn PDF document text
    • http://esllearningbydesign.com/app/webroot/files/file/41336076744.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/posororadivejatisamozupal.pdfIn PDF document text
    • http://parvazyab.net/basefile/api203/files/mofasezewasavetiw.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/d16eb716590d7dc632909c88d8b09aba/71296483607.pdfIn PDF document text
    • http://grafiport.com/userfiles/file/mejekibus.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/12363978186.pdfIn PDF document text
    • http://0975811252cool.linker.tw/files/8024411619.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/xetobebef.pdfIn PDF document text
    • https://marblobathware.ph/app/webroot/img/files/84703245317.pdfIn PDF document text
    • https://grafconsulting.pl/Upload/file/21737407605.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/c0ff03be2fb4ac9a7d449832513615c2/gisetetanufapazebowixus.pdfIn PDF document text
    • http://iknow.pl/files/file/zezegemovo.pdfIn PDF document text
    • https://davnosti.ru/upload/jirejenirusuw.pdfIn PDF document text
    • https://myparrotfood.com/user_files/files/dufosexajuxifitebozagivon.pdfIn PDF document text
    • https://ksi-system.pl/editorfiles/file/1961856648.pdfIn PDF document text
    • https://regaluxiluminacion.com/uploads/assets/file/tagufanidusigejoz.pdfIn PDF document text
    • http://metallpress.info/files/vajaxubanasula.pdfIn PDF document text
    • https://gencerenerji.com/resimler/files/radigaf.pdfIn PDF document text
    • https://jss-moms.si/upload/File/lakowa.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_off0000b502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB502 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cd14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD14 16800 bytes
SHA-256: 07e586b5b16432a034aff9ce596f98b0e91ca890269f871368beaa6e261871f3
font_02_sfnt_off0000f8b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B1 11056 bytes
SHA-256: 7a818176de5c98381a1ed9abce94a5ba8e8127cbc7966882f97de15f129c441d