Malicious PDF — malware analysis report

Static analysis result for SHA-256 8388019f0ccb74f1…

MALICIOUS

PDF

81.0 KB Created: 2021-09-09 08:01:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c725c1e7d9fc659c4b97f4cf9a6a544e SHA-1: 6dc25a2620b975466ee30582c5557b59b8bc8f10 SHA-256: 8388019f0ccb74f16a88ad1ca96ce7fc7ec055ade794fc55c3f631fcf33cd488
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple links to external resources, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to trick users into downloading further malicious content. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics supports the conclusion that this PDF is designed to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://limoride.net/gallery/file/40769920563.pdf In PDF document text
    • http://driver-jazda.pl/upload/file/40497347408.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/bamebejuw.pdfIn PDF document text
    • https://www.weldcor.ca/public/ckfinder/userfiles/files/fivonawavoxojunipepife.pdfIn PDF document text
    • https://hargagila.com/uploads/image/files/43323350130.pdfIn PDF document text
    • http://sanzmendia.com/userfiles/files/labinevadawok.pdfIn PDF document text
    • http://srsheicha.com/uploadfile/file/bipavaboxaxom.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/sigafiderutakukok.pdfIn PDF document text
    • https://dampinggame.com/calisma2/files/uploads/38351981632.pdfIn PDF document text
    • http://netmode.net/app/webroot/uploads/files/39349947646.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/88769291118.pdfIn PDF document text
    • https://ubk-sad.de/azubi/userfiles/files/suwofen.pdfIn PDF document text
    • https://cantellodetersiviprofessionali.it/uploads/file/49697912013.pdfIn PDF document text
    • http://orsini-blasioli.it/userfiles/files/98621779341.pdfIn PDF document text
    • http://podolsk-kondicionery.ru/upload_picture/file/finurugiboruxanugowovuji.pdfIn PDF document text
    • http://moskvaznaet.ru/upload/files/55992526040.pdfIn PDF document text
    • https://www.aukuras.org/ckfinder/userfiles/files/lijedob.pdfIn PDF document text
    • https://pokereshop.cz/data/file/36459253039.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/99282224561.pdfIn PDF document text
    • https://www.fangjin.org/ckfinder/userfiles/files/tutotarimo.pdfIn PDF document text
    • http://www.cafeinca.com/img/public/contenido/file/patunufeweseritom.pdfIn PDF document text
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/62348806736.pdfIn PDF document text
    • http://imapbook.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/jefamawufokibuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=gta+san+andreas+cheats+iphone+downloadPDF 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_off0000d62f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD62F 10736 bytes
SHA-256: af4fdbbbdd3dde6c376c4fa1ce13bb1c1586387273fd27b582d0d63e0e2f3b1d
font_01_sfnt_off0000eed7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEED7 18460 bytes
SHA-256: 0874b6d7076c163246a99c089df244269fc6a90f9bf1d8b3cf7827c6c1651ff7
font_02_sfnt_off00011e11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1