Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce471ec4db5071d1…

MALICIOUS

PDF

70.5 KB Created: 2021-05-28 02:54:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 8778db117006f8b89eedcdddd84c9c56 SHA-1: 15897f4ba0257e929b01e1b7dff5e045ba5855d5 SHA-256: ce471ec4db5071d19bd7287bc06f2f2a88f598cce64c306dde9cfb3361422355
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to various PDF files hosted on compromised websites, suggesting a phishing or credential harvesting attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, contains metadata related to resume and cover letter writing, likely serving as a lure.

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 http://www.jobsincrete.gr/images/_user_na/file/48448160203.pdf In PDF document text
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bcc1c2e306---82388100088.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071bf686b5e4---romepoxelinadi.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae3b69398fa---negenenileforoduk.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609b16dbadcf2---nigijipifogu.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/d09ec3dbf497fb743af2afb9a66c6a57/divajure.pdfIn PDF document text
    • http://angelojrobles.com/admin_initial_test/userfiles/file/muzewo.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074350200b35---xezab.pdfIn PDF document text
    • http://timeyear-v.com/userfiles/file/23873345009.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160aabd0ec86df---dakafexiwaxakoz.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607e1c35623b3---10205885112.pdfIn PDF document text
    • http://apsara.ru/userfiles/file/pokuditezibuxugopo.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/44834666897.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d7edfe3af6---wexufagosexexenore.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/marafupirake.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a76eca33975---34890500227.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/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+write+a+good+accounting+cover+letter+for+resumePDF link annotation
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a062726abaf---nosonelowotadevalasu.pdfIn 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d70f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD70F 5452 bytes
SHA-256: 66cd62b9b7ef9ceec452bdb6a2626033f67c12ae9d1adfe5cd5cf564dcf82ed6
font_01_sfnt_off0000e9a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9A7 10272 bytes
SHA-256: 7d842db167341dd6726e0f8125a3db3073fba88a91d55d680ef3e5bcb0f38f25