Malicious PDF — malware analysis report

Static analysis result for SHA-256 a331c6c42311f317…

MALICIOUS

PDF

76.9 KB Created: 2021-09-20 01:28:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 449d51b48c463cb60218e478ea31c770 SHA-1: bcc5033b593704b87647390744a47fb76c4d3e2e SHA-256: a331c6c42311f3177d33e9b0fee262b9088076b952c0aad631af4e8a984f5699
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is a PDF that contains a large number of links to other PDF files, many of which are hosted on disposable domains. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates that this is a link farm designed to obscure the true malicious intent. The presence of a ClamAV detection for 'Pdf.Phishing.Trojan' further supports the malicious classification. The overall pattern suggests a phishing or scam attempt using a link farm to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://usgcambodia.com/userfiles/file/zotedozerozogato.pdf In PDF document text
    • http://marleenjansen.nl/images/uploadfiles/zatugurosuritime.pdfIn PDF document text
    • https://smwebtechnology.com/arishayurveda.com/userfiles/file/lenexofimafikarunexi.pdfIn PDF document text
    • http://tpdw.pl/userfiles/file/46042056824.pdfIn PDF document text
    • http://shriadinathbank.com/uploads/49897806617.pdfIn PDF document text
    • https://kopari.hu/files/file/siromuninotunixeborewadok.pdfIn PDF document text
    • https://ontech.vn/images/ckeditor/files/85241360778.pdfIn PDF document text
    • http://zgkimsteszew.pl/img/upload/files/55715135205.pdfIn PDF document text
    • https://mgc.to/sites/web/upload/files/27837325361.pdfIn PDF document text
    • https://rosettes.it/userfiles/file/10189360405.pdfIn PDF document text
    • http://bellamy.tw/uploads/files/202109041758342231.pdfIn PDF document text
    • http://enslev-anlaegsservice.dk/userfiles/file/supixedevad.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16138d7395b184---sipoviwojigidinovaw.pdfIn PDF document text
    • https://zabulgaria.org/userfiles/file/nuxibuwopu.pdfIn PDF document text
    • http://dienlanhhuubinh.com/upload/files/dalifajuniwolaxigiwas.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ff8dface28---dopixazipelusuwujuxagidez.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/80340586674.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/93406764165.pdfIn PDF document text
    • http://muntepa.com/userfiles/files/92596394572.pdfIn PDF document text
    • http://antwerp-reefer-tournament.be/argt/files/94939415065.pdfIn PDF document text
    • https://nomaquito-travel.com/editor-images/batopesubotovugef.pdfIn PDF document text
    • http://itaxabc.com/userfiles/file/20210913191938_546559490.pdfIn PDF document text
    • http://bhk-aindling.de/userfiles/files/85350340195.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=download+gta+2+ps1PDF 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_off0000c6ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dee5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEE5 10500 bytes
SHA-256: 9ee74cf9e8a7a551643e821f0360260e842be6e9f1a8e68fbd1e3751b548b266
font_02_sfnt_off0000f6df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6DF 17840 bytes
SHA-256: 285d881ddb7b0ef8194b9ea2456fcef7db020c935ad67d0a99f06fef4e1d7539