Malicious PDF — malware analysis report

Static analysis result for SHA-256 10a3733332f0c206…

MALICIOUS

PDF

86.0 KB Created: 2021-06-17 15:53:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 1c4e59b53299922228e4be37c1e38724 SHA-1: 0b8e83de1b3bcead222b9f97294f581de5c08dfd SHA-256: 10a3733332f0c206f430d6d44befb29a6dfdd581b825ac9568131d2ac99bf15f
156 Risk Score

Malware Insights

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

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 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 https://synerhu.ru/uplcv?utm_term=linear+equation+exercises+with+answers PDF link annotation
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16075c662850c2---92026548281.pdfIn PDF document text
    • https://www.chartsunlimited.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/160945a9d04577---6411430115.pdfIn PDF document text
    • https://watfordfairtrade.org/app/webroot/img/files/devediditokib.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/42945725c80abb634d67f4389f0bdc4a/dixinupujeterig.pdfIn PDF document text
    • http://jonkmp.nl/img/cms/file/riwixut.pdfIn PDF document text
    • http://artgraf24.pl/userfiles/file/9476671713.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/unplg0k1suhkuo84cvh1gkijj5/6364189592.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/83470785107.pdfIn PDF document text
    • http://foodchemsino.com/d/files/13582877566.pdfIn PDF document text
    • http://noithatnhapkhaugiasi.com/luutru/files/zenimoduzet.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1608f645cbf65f---97155474774.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/j78m0k0r9rl19s8kooua6gl398/79172126563.pdfIn PDF document text
    • https://www.karavanlakesfet.com/wp-content/plugins/super-forms/uploads/php/files/62c39bb268b415bb968535861f485258/lekiwadimujalijaxo.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/37420f16187cee95fbf1fb095bef36c5/66399282814.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a23a3455d---24790392141.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000fd0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD0C 5084 bytes
SHA-256: 61e28c6afad6f6d7ef60bed4492a9986cec3fd5bb3f33639f82e582c3ef038ea
font_01_sfnt_off00010e71.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E71 11468 bytes
SHA-256: dce225a10376db95e17e1ca172e3dd5e587d1140c7f0c5695f1722045ddea9b4
font_02_sfnt_off000135a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135A2 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e