Malicious PDF — malware analysis report

Static analysis result for SHA-256 e44e88fc7595610d…

MALICIOUS

PDF

98.4 KB Created: 2021-06-09 21:49:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 799422840a9c1605aaabfd356058cca5 SHA-1: 61b25f5551e8a5a833bb0f1ba80610a145cba434 SHA-256: e44e88fc7595610dc3c18598848b6435e764a9f50848f718e100e61daa17bf9e
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including a critical ClamAV detection for Pdf.Phishing.Trojan and an ML classifier indicating maliciousness. It contains numerous external links, many pointing to compromised WordPress upload directories, suggesting a link farm or phishing lure. The embedded content, though heavily obfuscated, likely facilitates the redirection to these malicious URLs, which are the primary IOCs.

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://crysiq.ru/uplcv?utm_term=accuracy+and+precision+in+measurements+lab+answers PDF link annotation
    • https://samiznojmo.cz/wp-content/plugins/super-forms/uploads/php/files/c88325612c3bb84c70d5f7bedd397e28/baxazijidekewa.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/160870ca99da06---wibasewexatexeruxinulopu.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d2d4021d44---kuruvolejugi.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/72264241886.pdfIn PDF document text
    • http://kowel.com/ckfinder/userfiles/files/1622436769.pdfIn PDF document text
    • http://florylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tuvisilosuzobezid.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/16073a5ce2dc46---lowiduvegazadikipasa.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e56ed0912---rasut.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160abf46daf508---89959244292.pdfIn PDF document text
    • http://redwoodpwr.com/wp-content/plugins/super-forms/uploads/php/files/ak0qumc3n079eelsqqlmeodpj4/34745122863.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/6035f2a8302b9f685f672e8ffa93823c/zamape.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16082c27bb6d95---29304942743.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/fbtfrq9p40q95d6rala9742lis/42274112666.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2866b4c07---dobutijugumagazajomej.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a2bc4e695f3---lepirenikilexiluduwabo.pdfIn PDF document text
    • http://digimaap.com/wp-content/plugins/super-forms/uploads/php/files/eble59cicus3jn0i30kfqjn3nd/puwol.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000142b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142B3 5540 bytes
SHA-256: 8ce0923fb35babd33e8d5a8273e8aa7b0527791f432811be212398365a3a303a
font_01_sfnt_off00015586.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15586 11452 bytes
SHA-256: 6b0f6303bd0c430ab4b9554d541d207d895801538a297a85dfe631faa4e48802