Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa255b9e8ad714a7…

MALICIOUS

PDF

84.0 KB Created: 2021-09-22 14:24:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: a36d38de5f697f7b8c58647b2db8edb6 SHA-1: 7c6d696ade7bd31287f38aaab961a194663a858b SHA-256: aa255b9e8ad714a7402eb7908957159ac0acbdb8f05000f7b2c5c873530764b0
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of external URIs and the link farm heuristic suggest an attempt to direct the user to a compromised or malicious website.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://drafthe.ru/uplcv?utm_term=zero+to+one+book+summary+pdf PDF link annotation
    • http://eapver.com/upload/ckimg/files/202109131802328331.pdfIn PDF document text
    • http://golfproradost.cz/webpagebuilder/ckfinder/userfiles/files/lunupewelenuliziwasa.pdfIn PDF document text
    • https://phatgiaolongan.com/upload/ckupload/files/39364821071.pdfIn PDF document text
    • https://onwater.my/uploads/file/62543242862.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146a86523e68---baruvadovetu.pdfIn PDF document text
    • http://cybernet.asia/UserFiles/File/2385981239.pdfIn PDF document text
    • https://anzhero-sudzhensk.verlauf-ekb.ru/admin/ckfinder/userfiles/files/xotirawedovozuj.pdfIn PDF document text
    • https://angkortaxiservice.com/userfiles/file/67039321687.pdfIn PDF document text
    • https://kampusogrenciyurdu.com/file/xebop.pdfIn PDF document text
    • http://domadoma.cz/userfiles/file/zufomapetalotepiwiwugi.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/58394387330.pdfIn PDF document text
    • https://creativenursery.net/home/creative/public_html/ckfinder/userfiles/files/8312402551.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/63109489181.pdfIn PDF document text
    • https://mygenius.ru/admin/ckfinder/userfiles/files/kinigiropidejifeselonudog.pdfIn PDF document text
    • http://punaide.com/userfiles/files/jolewigomuzemuse.pdfIn PDF document text
    • http://fzsvybbs.at/userfiles/file/buturovopelosezum.pdfIn PDF document text
    • http://oilspecchem.com/files/96946002464.pdfIn PDF document text
    • https://mklaassen.nl/images/file/dinisunowime.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/nesizuxijerafovesugixa.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/29514275363.pdfIn PDF document text
    • http://massarentearchitettura.com/userfiles/files/lupaleforilebebuzupelul.pdfIn PDF document text
    • http://patanamachine.com/imgUpload/files/tugodanolurowanebomarek.pdfIn PDF document text
    • http://sfalojistik.com/userfiles/file/80786191825.pdfIn PDF document text
    • https://sportuna.be/ckfinder/userfiles/files/dumozizezetegudesulufe.pdfIn PDF document text
    • http://alessandrotria.altervista.org/areap/ckfinder/userfiles/files/dixawomo.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_off0000e36c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE36C 17656 bytes
SHA-256: 9bf669a748c068bda0088d3485d9a15781dc8645dd6977e3c8d2bc61441d1f46
font_01_sfnt_off00011111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11111 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12928 10932 bytes
SHA-256: 06a756dad645dc62576cb316d7ce112d6f9ad9c59ac80584525acf03bc843e4d