Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4e19cdf32920285…

MALICIOUS

PDF

85.2 KB Created: 2021-07-07 03:57:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: a328893384460a47d0f131ff7a8805e3 SHA-1: 62c54f1c543d28ee0be3d137499a36bfe1f32062 SHA-256: b4e19cdf32920285de83785e35f993a0fdfad5e93c768c9b4644f04603ca694c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating the document is designed to drive traffic to potentially malicious or compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160719a57e2536---zapefi.pdf In PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f059d33f80---likugubezabo.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a2428668cc2---1878643441.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/pavidesaxelelufamupowed.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160884092c77e0---55451497817.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607885cf2c1e1---jewoneke.pdfIn PDF document text
    • http://bukhatirhomes.com/userfiles/file/vavumovevixelofomof.pdfIn PDF document text
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/160820ed9961e8---23774531900.pdfIn PDF document text
    • https://forkidsvietnam.vn/wp-content/plugins/super-forms/uploads/php/files/q806pgf2j8kcbl2ui2iglfl85i/95791504443.pdfIn PDF document text
    • http://anatolianlgs.com/userfiles/file/30808332593.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/dovipe.pdfIn PDF document text
    • https://mobiligennari.com/userfiles/file/82761393528.pdfIn PDF document text
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/e545f11e2f8f394a61a840ca01de0c50/66128485357.pdfIn PDF document text
    • http://maihome.hu/admin1/file/71710123684.pdfIn PDF document text
    • https://www.diktu.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c655637852---vowiwi.pdfIn PDF document text
    • https://mwasafat.com/uploads/files/guzanutudutejasogujara.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b20833a7560---97736298647.pdfIn PDF document text
    • https://www.paparazzirestaurant.com.au/wp-content/plugins/super-forms/uploads/php/files/6faff530598a4391d46f642254f6f1b1/lefuwisumepunuti.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/57c43f10190f3f2ef9d8daae3f906367/zodonefefokiforexipozepos.pdfIn PDF document text
    • http://www.barankayalar.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1609c85342c5c6---kitisetirimilodov.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160e14e6ea9858---54926500697.pdfIn PDF document text
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/fd0fbdcf6de79cc6351dae8b5fe8707e/vojomifet.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16083ed283ad53---wiwujemerokikokurubajusa.pdfIn PDF document text
    • https://iphonerepairservice.nl/app/webroot/files/userfiles/files/fenazi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=workplace+health+and+safety+inspection+checklistPDF 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_off0000e704.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE704 10916 bytes
SHA-256: d4f03bb591f5355aebd12e4440fa77cd3080eec5a28d69a211744e3be1eaed8f
font_01_sfnt_off00010048.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10048 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001185a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1185A 17352 bytes
SHA-256: 5532e8ccd142ab08bf99325d6d3bc0e2048a4c6c58b3cbae79fb50859e2d99db