Malicious PDF — malware analysis report

Static analysis result for SHA-256 297c4b6afa0312ab…

MALICIOUS

PDF

88.3 KB Created: 2021-06-14 11:53:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 7cde203191d7709fdcb59b14e92c7eab SHA-1: 2ef2626c248685aee298b60d668ee09cd8240c1e SHA-256: 297c4b6afa0312ab81c2c2841a1f2bb0d5717313c733b0cf6021c59cb6198bd7
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS upload directories or are part of a link farm hosted on disposable domains. The document body, though heavily obfuscated, contains strings related to 'wkhtmltopdf' and a URL that aligns with the heuristic findings, suggesting a deliberate attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.8644

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://pixomot.ru/uplcv?utm_term=thousand+sons+9e PDF link annotation
    • http://www.assignproject.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609da0c1eb599---16505071852.pdfIn PDF document text
    • http://atthaya.com/file_media/file_image/file/zilarut.pdfIn PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a0ecc53ef9---99654798436.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/1d0cba41b0db4d22b7f498a3c3a92afc/38577220283.pdfIn PDF document text
    • http://webscape.co.bw/wp-content/plugins/formcraft/file-upload/server/content/files/16080a11ba14a0---jujazem.pdfIn PDF document text
    • http://dharmapremipariwar.org/userfiles/file/88919293978.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/o7aoaa7l1knaqki76t2ojemf4s/garasuwemila.pdfIn PDF document text
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607428e16ce10---48422630208.pdfIn PDF document text
    • http://sweetbasketsbyjackie.com/clients/864293/File/kopiluzijevu.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/ferjii1b2ag72j4ifthkn7o2d5/49970927342.pdfIn PDF document text
    • http://micronforgacsolo.hu/UserFiles/file/nopagawu.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-5-17/20210517111147685353.pdfIn PDF document text
    • http://telekommarketing.com/firme_data/files/wagotezisotiviju.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a09e22af87---717197886.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/bc0e0900bdc7b4382148d60cc9a8a486/23772227951.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160859d0b8677c---91708406924.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn 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_off00011323.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11323 4888 bytes
SHA-256: a8394c22175f436d8b18ccd461abd79033d52d6b9a52297958eedead64fbeaac
font_01_sfnt_off000123b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123B9 11132 bytes
SHA-256: e6072c5137cbb9b4b0cc52b85c4e2c21caeec9583806f1199e057f20df4f5f89
font_02_sfnt_off000149a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149A6 16060 bytes
SHA-256: d1a84ba8f0e4a827a048d387db8dd5dae3538f1c7e72415b16af587a9947cdc7