Malicious PDF — malware analysis report

Static analysis result for SHA-256 28e612b55bb90a8f…

MALICIOUS

PDF

69.4 KB Created: 2021-10-03 21:10:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: e96d318ecaadce7e8929fb492871dcd3 SHA-1: 3e064bd7a140d227091bcf3eca9800f871ab53fb SHA-256: 28e612b55bb90a8f3e97a37d749b955f93e68829f74d5a88c70d8bcb8a42ea8e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the nature of the URLs and the heuristic firings point towards a phishing or redirection attack, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://janjoling.com/public/ckfinder/userfiles/files/vagina.pdf In PDF document text
    • http://108shiva.com/userfiles/file/In PDF document text
    • http://bhartiyambeohari.in/userfiles/file/6295966535.pdfIn PDF document text
    • https://bustotoronto.com/userfiles/file/vubawusexubidumaru.pdfIn PDF document text
    • http://aburobocon2019.mnb.mn/uploads/files/ripegarajike.pdfIn PDF document text
    • http://murielbellhomes.com/userfiles/files/ruzeveneraxefafigabaxeb.pdfIn PDF document text
    • http://npi-management.com/ressource/site-image/files/xikinotobapekajodigedu.pdfIn PDF document text
    • http://tjjjsh.com/uploads/files/wefejodezugogi.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614879d48b654---dulid.pdfIn PDF document text
    • https://ooo-kenk.ru/userfiles/file/pitotumegumura.pdfIn PDF document text
    • https://udruga-invalida.hr/files/62156207872.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/tozalo.pdfIn PDF document text
    • http://fujiya-la.com/uploads/files/85145830448.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615710eec7b1a---debatemixa.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/xumibe.pdfIn PDF document text
    • http://cocoon-source-harmonie.fr/public/file/74378266830.pdfIn PDF document text
    • http://sp3siemianowice.pl/userFiles/files/busumabivuminebuzobajog.pdfIn PDF document text
    • http://donkaew-furniture.com/ckfinder/userfiles/files/12556380123.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/ranemowi.pdfIn PDF document text
    • https://rougezenekar.hu/files/file/83002423983.pdfIn PDF document text
    • http://circolosilverblufitnessclub.eu/userfiles/files/fupapiluxologo.pdfIn PDF document text
    • https://fotojursa.cz/userfiles/file/fepatoxodaweviwij.pdfIn PDF document text
    • https://microfocus-realize2020mea.com/wp-content/plugins/super-forms/uploads/php/files/3f83503fc8eb00644a153e8951a53640/getupiputun.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/55999022381.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=is+there+a+comma+before+yet+at+the+end+of+a+sentencePDF 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_off0000af6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF6C 10808 bytes
SHA-256: a0a155357edc29aa942acce5cda5b32b915ce78a1d9bd3b7fbb2079a911ad719
font_01_sfnt_off0000c834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC834 15632 bytes
SHA-256: 9eee4b29d8722b9b2f8a270dcc45e2c25a5791357a5009405ce27b97d0e25833
font_02_sfnt_off0000efc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1