Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f9207d7efa0dea1…

MALICIOUS

PDF

76.4 KB Created: 2021-05-13 12:47:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: bb3eea49bebbe1c4ced4fd757738ab4f SHA-1: 2d124baccb21cbe8e5383820364507855e45e350 SHA-256: 4f9207d7efa0dea1d41a658160dad0c75b22cf7bac6a55c3291ce196471db6ce
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many hosted on compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the presence of external links and the heuristic firings point towards a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 https://oniceh.ru/uplcv?utm_term=multiplying+fractions+coloring+worksheets+pdf PDF link annotation
    • http://bestapp4u.com/admin/uploadedfiles/file/83732845175.pdfIn PDF document text
    • https://www.letspassdriving.co.uk/wp-content/plugins/super-forms/uploads/php/files/bo0rvhc0p5qiknqtqd1ii32atf/toxunisugujoguvobapamuke.pdfIn PDF document text
    • https://lsp.od.ua/wp-content/plugins/super-forms/uploads/php/files/psosndsji4up9kggpjfsgveaj4/josarir.pdfIn PDF document text
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/guhl1oejo7rpa9596ke0n3v84f/95646780047.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/mdqe7v1jajgfd59lr3qhfdtc67/12565223181.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/hmsc0nnkmiro0vne9ajkjml3q4/75401252970.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/ae265bfa71c496dba3a15bb62c114e8c/dosewejeb.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/febosolazipuno.pdfIn PDF document text
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/qh20005qka6pdatn2skicss00b/95979621542.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160907eca294ba---fafavogolimizenevajof.pdfIn PDF document text
    • http://agiusfuneraldirectors.com/files/file/wufabozefum.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/8698aa629486967202156777b5b590d7/jiladovedufinipow.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcb8a85f7e---fuputukojizalapoxajexonen.pdfIn PDF document text
    • http://mulroyenvironmental.ie/userfiles/file/81707548022.pdfIn PDF document text
    • http://notarbrazda.cz/userfiles/file/84686410720.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dd3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD3E 5564 bytes
SHA-256: 51caa097c3e2c547aff229057914aff7571d731f182c58ffc920f22cfc5c1a7c
font_01_sfnt_off0000f037.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF037 10664 bytes
SHA-256: c779f8cf42fed6ca2d490ff6ce1e8d91ad4fbf3b828ccee7ebe1532fead86d75
font_02_sfnt_off000114c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114C6 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176