Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c24c1dafb26b9c7…

MALICIOUS

PDF

78.8 KB Created: 2021-09-06 19:58:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: bd361c8d26c433e38e49072be4903cc6 SHA-1: 7d38367d5401d2987e5837d20a8fe07a92c91cbe SHA-256: 1c24c1dafb26b9c70739b9fe141e0a3185d032da390c10ddce6368cdf714d7fb
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e951c2564d8---53499250654.pdf In PDF document text
    • http://naturallabs.de/userfiles/file/93696099097.pdfIn PDF document text
    • https://interstudy.net/userfiles/file/7107844036.pdfIn PDF document text
    • http://lnianemarzenie.pl/userfiles/file/jinipomixidomi.pdfIn PDF document text
    • http://pokewaveanaheim.com/uploads/files/wapevugavefofe.pdfIn PDF document text
    • https://www.brightfieldbusinesshub.co.uk/wp-content/plugins/super-forms/uploads/php/files/clooo4ovu7as61nhsnogiqh8v2/guxitu.pdfIn PDF document text
    • http://aps-mes.com/files/file/xevubipulubekuferup.pdfIn PDF document text
    • http://wasserburg.pl/userfiles/file/48893803918.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c884c653650---nakejalakosegagidinonaviv.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c4b540e9a91---gawoxepolafibawok.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/komezafivitewevumef.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/femukotipokalewasifezej.pdfIn PDF document text
    • http://tanabuauto.com/js/upload/files/zomux.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/154415804060be66d2900cc.pdfIn PDF document text
    • https://movesforfree.com/wp-content/plugins/super-forms/uploads/php/files/nv6ld1ndg0uskts0n6btock3d5/56688971901.pdfIn PDF document text
    • https://jobtiara.com/files/files/zewulifekod.pdfIn PDF document text
    • http://cortabellanews.com/userimages/kepumepag.pdfIn PDF document text
    • http://lctrading-gmbh.com/ckfinder/userfiles/files/zekadawa.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607daa66b7db0---51678223228.pdfIn PDF document text
    • http://partnercable.hu/files/19950420131.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=guardianship+act+nsw+pdfPDF 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_off0000cd4b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD4B 18184 bytes
SHA-256: a206cbd79e64adac41a3816da54435e00d0bc8e7a9ad65ab842e3fec9dc651b0
font_01_sfnt_off0000fd5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD5B 10644 bytes
SHA-256: 978f063b5098c2dee297a0c9b6496554cb5568a3f9b8528aa02208b98b127c2d
font_02_sfnt_off000115b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1