Malicious PDF — malware analysis report

Static analysis result for SHA-256 750f1736d5f3c085…

MALICIOUS

PDF

73.3 KB Created: 2021-06-13 01:18:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 446925844728543face65c6d1fdba0ac SHA-1: eaacca0f6f8aa81943fff3acddd15611db2e7883 SHA-256: 750f1736d5f3c08542b9f1c92428dc4681ee6050fd6c76c894e86de27c94df26
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. It contains multiple links to external websites, some of which are hosted on compromised CMS uploads, suggesting a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains metadata related to 'The vanishing half book club questions' and 'wkhtmltopdf', indicating a potential lure.

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://irlanc.ru/uplcv?utm_term=the+vanishing+half+book+club+questions PDF link annotation
    • http://jikaramen.com/uploads/files/64018647694.pdfIn PDF document text
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160acf9aa39ac9---gejevejumapine.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/ojr7dh626e33l6p65dqc4vfq1g/20124969649.pdfIn PDF document text
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/0d5a27c0eb71344cb6d9973ea451d2f8/laxigumadudakapaxev.pdfIn PDF document text
    • https://journeypeople.cc/wp-content/plugins/super-forms/uploads/php/files/9f5a572d6e503c9f4efd73a0aa30fc01/fubatapuv.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e1a40bae92---nuzuv.pdfIn PDF document text
    • https://leesman.com/wp-content/plugins/super-forms/uploads/php/files/af9366defae3abf7cc9a95d8d42e2c79/86546380582.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/2uksagf8ehbbfgs1l9ft4bfo25/xudanajoweneka.pdfIn PDF document text
    • http://mwflower.com/upimagesfile/%5C/tekobulo.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e976cc7f03---tewejilerevitonovikakete.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a3ef70ae5a8---3899274957.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160774046435e3---mimikojonizitikap.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bdbae3ade98---kapifizamagexamub.pdfIn PDF document text
    • http://www.elitagida.com.tr/wp-content/plugins/super-forms/uploads/php/files/dktt7lkfucou0l5o3o4t4nj0i6/dewufegazavafima.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_off0000e015.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE015 5384 bytes
SHA-256: bf9eb0b5a0fcd12c64f7b5944e2d1970ffea03d3a424834c0d89da227521f29a
font_01_sfnt_off0000f277.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF277 10736 bytes
SHA-256: 08713507a90ecf67ab079819b3c706645c79cbfce14386b2b98d430031b0c101