Malicious PDF — malware analysis report

Static analysis result for SHA-256 b39b66ab82765bf4…

MALICIOUS

PDF

66.3 KB Created: 2021-05-26 13:19:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 96ca68b21d710aad7320076119602f2a SHA-1: 026db82a9246d528ce955b675fa9f193b2fd23d3 SHA-256: b39b66ab82765bf4ac2f2c20c603bf7119f6f65e88c1a1f2c2a41af651d6fc1a
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 0.9998

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://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/q6u14m902npi8tsljb2cvjh6g8/fenezavulefi.pdf In PDF document text
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/3f51db927c046e7dd413d53b547b379d/96311953376.pdfIn PDF document text
    • http://www.recetasyconsejos.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090635827c8d---vulisidusajuboluvonuka.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/99fb459096afd075e274a4a31be4baee/vofel.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086dd18f0d79---zofutolitemifi.pdfIn PDF document text
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/298aa5510733d1f3542ecb40bc6b69f0/48281699420.pdfIn PDF document text
    • https://eyetracking.pl/userfiles/file/zezewadoworazuboduxe.pdfIn PDF document text
    • https://acgroupenterprise.com/userfiles/file/desuvusogaleg.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098fbaac3897---fuvutitiragotet.pdfIn PDF document text
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609998f688ebf---jumuxabuziles.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078ddb31f70d---93622749756.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607317714f584---waguk.pdfIn PDF document text
    • http://turagent007.ru/userfiles/file/lugeburarugudil.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/tda4sd6pj7cs5379cdsqqe79i2/fesuxubevaxotig.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/9too3i532digfc028ro4mphpr6/78939058006.pdfIn PDF document text
    • http://sl-light.ru/design/img/upload/file/63327690605.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=ver+que+pena+tu+familia+online+gratisPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c3da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3DA 5312 bytes
SHA-256: a75cd8b29d8806d2fd586a27209f6b46540efd5b9dd060aa963ec49f6c2e2575
font_01_sfnt_off0000d5e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5E0 11144 bytes
SHA-256: 48fe17300edbae73ad75c494fc2148a4c1070e8d67b9bd1558b5f886e175ce64