Malicious PDF — malware analysis report

Static analysis result for SHA-256 70c96cff10b16457…

MALICIOUS

PDF

98.1 KB Created: 2021-07-24 04:59:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 8fc990bb31176d85ed332642e7cf01e3 SHA-1: 2a7f20f1f25db73807f76d54ffbafbcc8d194b3a SHA-256: 70c96cff10b16457949792987555bfcef16e7fef0f17d0d9850e3ecbbc9f3570
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF that leverages a link farm hosted on compromised WordPress sites to direct users to malicious PDF files. The heuristic 'SE_INVOICE_LURE' suggests the document's content is designed to mimic an invoice or payment request, encouraging users to click the provided links. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a phishing payload or further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 7

  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086752eeb4e8---luwofurebi.pdf In PDF document text
    • https://www.synergyheart2heart.team/wp-content/plugins/super-forms/uploads/php/files/i4esuhaecl015eclnpbemu8g0r/82505708556.pdfIn PDF document text
    • http://www.instalacionescueto.com/nueva/ckfinder/userfiles/files/21034742956.pdfIn PDF document text
    • http://catgarner.com/clients/873270/File/dewiw.pdfIn PDF document text
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607727766834a---41103126767.pdfIn PDF document text
    • http://jakebenmd.com/clients/0/0e/0eef9d569b11303d075d19626cc6f958/File/74893778765.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c87276e1a11---xadugogovix.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16087dc702f783---figazon.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ac4eb5c1468---bopudasinebupadekegupas.pdfIn PDF document text
    • http://dermatologomiguelgallego.com/miguel/fck/file/sasur.pdfIn PDF document text
    • https://kodcomputers.ro/2664/uploads/18557927903.pdfIn PDF document text
    • https://capital-tic.com/upload/ckfinder_temp/files/20210610183330.pdfIn PDF document text
    • http://uspeh-kursk.ru/ckfinder/userfiles/files/714660116.pdfIn PDF document text
    • https://cochleartudaskozpont.hu/files/1342085969.pdfIn PDF document text
    • https://bobecoingatlan.com/uploads/editor/file/wejebo.pdfIn PDF document text
    • http://posekatzahradu.cz/files/file/89608934741.pdfIn PDF document text
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/9e23e1dbc3f0bfb00011b779dc745ce2/fodiponozupoxuzerejijuwit.pdfIn PDF document text
    • http://xinyuemu.net/assets/202106/files/20210628210700869852.pdfIn PDF document text
    • http://groupkaishan.com/d/files/53258964187.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/kefuwezopoxopividewi.pdfIn PDF document text
    • http://dalaichau.com/files/lomake.pdfIn PDF document text
    • https://www.dishdivvy.com/wp-content/plugins/super-forms/uploads/php/files/e1535cf6d4f8c7ef7cdf09f47c48fb19/38933680344.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/ni384ouqtrbvvajkl5derimrnq/rokozesipofitivopovax.pdfIn PDF document text
    • http://amexeuro.com/an3_Uploads/file/67922692305.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=recent+trends+in+operations+management+pdfPDF 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_off00011d2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D2D 16816 bytes
SHA-256: 789d6e279f98089e727ce56a7fda7adcbab9f57918fcbb69885942580fcf15d4
font_01_sfnt_off000148fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x148FA 10960 bytes
SHA-256: 487b42c03bbd548cbe7f40474caa9afd426d57db702aa0fffc332711914c207f
font_02_sfnt_off0001623a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1623A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1