Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cd8d2b0b9969845…

MALICIOUS

PDF

72.6 KB Created: 2021-08-23 10:03:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: bfba23994d2151b40ab09990777c47aa SHA-1: 21fe5eccdaa097755f5ecf30a51265f343474cdf SHA-256: 4cd8d2b0b9969845000e6847de782a650056405a02942d9c94d217a85bcd281a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.lavalledesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607803b810912---88769322487.pdf In PDF document text
    • http://imtac.net/upload/files/9478014031.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/55133240311.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160aa7865e6169---guvinasepixigej.pdfIn PDF document text
    • https://www.demetagras.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8e36c6265---58548592054.pdfIn PDF document text
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc83a40ead2---12099911353.pdfIn PDF document text
    • https://curewelldiabetes.com/userfiles/file/37047277900.pdfIn PDF document text
    • https://art-lamps-rali.eu/files/file/71480307427.pdfIn PDF document text
    • https://netkat.in/ckfinder/userfiles/files/42909951517.pdfIn PDF document text
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/520016884a93960d56c6888cd940b54a/mofur.pdfIn PDF document text
    • https://noddy.nu/images/file/fifuseru.pdfIn PDF document text
    • https://dailyhondaotomientay.com/upload/files/magonefupabizupu.pdfIn PDF document text
    • http://gojjang.com/uploads/files/65590001599.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/adj8trki9ukhl88q498itvkro2/51688030419.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1608f420020695---zigususoxidexefogaj.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f63d53fe9b868cce39fe57ad7d5801bb/xexesupufet.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/cb505e33cdef775b26b52b2b27b212f2/61358149421.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=sedra+smith+microelectronic+circuits+6th+edition+pdf+free+downloadPDF 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_off0000b6ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6EE 16740 bytes
SHA-256: febbee916bd8c4df76e399f2d3ade662fadbb971eacc6050206798462d97cf9d
font_01_sfnt_off0000e1f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1F1 11312 bytes
SHA-256: 21ae733bd3d09ecc854611129d9fdbaeaecb2cfbab3c9a02049d3de2bd10ee96
font_02_sfnt_off0000fc5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC5E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1